diff --git src/wp-includes/class-wp-rewrite.php src/wp-includes/class-wp-rewrite.php
index 035bbc3..467f823 100644
--- src/wp-includes/class-wp-rewrite.php
+++ src/wp-includes/class-wp-rewrite.php
@@ -842,6 +842,30 @@ class WP_Rewrite {
 	}
 
 	/**
+	 * Adds or updates existing rewrite tags (e.g. %postname%).
+	 *
+	 * If the tag already exists, replace the existing pattern and query for
+	 * that tag, otherwise add the new tag.
+	 *
+	 * @since 4.5.0
+	 * @access public
+	 *
+	 * @see WP_Rewrite::$rewritecode
+	 * @see WP_Rewrite::$rewritereplace
+	 * @see WP_Rewrite::$queryreplace
+	 *
+	 * @param string $tag Name of the rewrite tag.
+	 */
+	public function remove_rewrite_tag( $tag ) {
+		$position = array_search( $tag, $this->rewritecode );
+		if ( false !== $position && null !== $position ) {
+			unset( $this->rewritecode[ $position ] );
+			unset( $this->rewritereplace[ $position ] );
+			unset( $this->queryreplace[ $position ] );
+		}
+	}
+
+	/**
 	 * Generates rewrite rules from a permalink structure.
 	 *
 	 * The main WP_Rewrite function for building the rewrite rule list. The
diff --git src/wp-includes/rewrite.php src/wp-includes/rewrite.php
index 7f3b2ed..826ced2 100644
--- src/wp-includes/rewrite.php
+++ src/wp-includes/rewrite.php
@@ -173,6 +173,21 @@ function add_rewrite_tag( $tag, $regex, $query = '' ) {
 }
 
 /**
+ * Removes an existing rewrite tag (like %postname%).
+ *
+ * @since 4.5.0
+ *
+ * @global WP_Rewrite $wp_rewrite WordPress rewrite component.
+ * @global WP         $wp         Current WordPress environment instance.
+ *
+ * @param string $tag Name of the rewrite tag.
+ */
+function remove_rewrite_tag( $tag ) {
+	global $wp_rewrite;
+	$wp_rewrite->remove_rewrite_tag( $tag );
+}
+
+/**
  * Add permalink structure.
  *
  * @since 3.0.0
diff --git src/wp-includes/taxonomy.php src/wp-includes/taxonomy.php
index 8cbef3c..02ac213 100644
--- src/wp-includes/taxonomy.php
+++ src/wp-includes/taxonomy.php
@@ -473,6 +473,61 @@ function register_taxonomy( $taxonomy, $object_type, $args = array() ) {
 }
 
 /**
+ * Unregister a taxonomy.
+ *
+ * @since 4.5.0
+ *
+ * @global WP_Rewrite $wp_rewrite    WordPress rewrite component.
+ * @global WP         $wp            Current WordPress environment instance.
+ * @global array      $wp_taxonomies List of taxonomies.
+ *
+ * @param string $taxonomy Taxonomy name.
+ * @return bool True on success, false on failure.
+ */
+function unregister_taxonomy( $taxonomy ) {
+	if ( ! taxonomy_exists( $taxonomy ) ) {
+		return false;
+	}
+
+	$taxonomy_args = get_taxonomy( $taxonomy );
+
+	// Do not allow unregistering internal taxonomies.
+	if ( $taxonomy_args->_builtin ) {
+		return false;
+	}
+
+	global $wp_taxonomies, $wp_rewrite, $wp;
+
+	// Remove query vars.
+	if ( false !== $taxonomy_args->query_var ) {
+		$wp->public_query_vars = array_diff( $wp->public_query_vars, array( $taxonomy_args->query_var ) );
+	}
+
+	// Remove any rewrite rules, permastructs, and rules.
+	if ( false !== $taxonomy_args->rewrite ) {
+		remove_rewrite_tag( "%$taxonomy%" );
+		unset( $wp_rewrite->extra_permastructs[ $taxonomy ] );
+	}
+
+	// Unregister callback handling for metabox.
+	remove_all_actions( 'wp_ajax_add-' . $taxonomy );
+
+	// Remove the taxonomy.
+	unset( $wp_taxonomies[ $taxonomy ] );
+
+	/**
+	 * Fires after a taxonomy is unregistered.
+	 *
+	 * @since 4.5.0
+	 *
+	 * @param string $taxonomy Taxonomy name.
+	 */
+	do_action( 'unregistered_taxonomy', $taxonomy );
+
+	return true;
+}
+
+/**
  * Builds an object with all taxonomy labels out of a taxonomy object
  *
  * Accepted keys of the label array in the taxonomy object:
diff --git tests/phpunit/includes/testcase.php tests/phpunit/includes/testcase.php
index a468deb..f9a98da 100644
--- tests/phpunit/includes/testcase.php
+++ tests/phpunit/includes/testcase.php
@@ -171,7 +171,7 @@ class WP_UnitTestCase extends PHPUnit_Framework_TestCase {
 	 */
 	protected function reset_taxonomies() {
 		foreach ( get_taxonomies() as $tax ) {
-			_unregister_taxonomy( $tax );
+			unregister_taxonomy( $tax );
 		}
 		create_initial_taxonomies();
 	}
diff --git tests/phpunit/includes/utils.php tests/phpunit/includes/utils.php
index 0a6dfc1..47b6885 100644
--- tests/phpunit/includes/utils.php
+++ tests/phpunit/includes/utils.php
@@ -333,10 +333,6 @@ function _unregister_post_type( $cpt_name ) {
 	}
 }
 
-function _unregister_taxonomy( $taxonomy_name ) {
-	unset( $GLOBALS['wp_taxonomies'][$taxonomy_name] );
-}
-
 /**
  * Unregister a post status.
  *
@@ -398,7 +394,7 @@ class wpdb_exposed_methods_for_testing extends wpdb {
  */
 function benchmark_pcre_backtracking( $pattern, $subject, $strategy ) {
 	$saved_config = ini_get( 'pcre.backtrack_limit' );
-	
+
 	// Attempt to prevent PHP crashes.  Adjust these lower when needed.
 	if ( version_compare( phpversion(), '5.4.8', '>' ) ) {
 		$limit = 1000000;
@@ -410,7 +406,7 @@ function benchmark_pcre_backtracking( $pattern, $subject, $strategy ) {
 	for( $i = 4; $i <= $limit; $i *= 2 ) {
 
 		ini_set( 'pcre.backtrack_limit', $i );
-		
+
 		switch( $strategy ) {
 		case 'split':
 			preg_split( $pattern, $subject );
diff --git tests/phpunit/tests/category.php tests/phpunit/tests/category.php
index 913f4dc..730f5d5 100644
--- tests/phpunit/tests/category.php
+++ tests/phpunit/tests/category.php
@@ -10,7 +10,7 @@
 class Tests_Category extends WP_UnitTestCase {
 
 	function tearDown() {
-		_unregister_taxonomy( 'test_tax_cat' );
+		unregister_taxonomy( 'test_tax_cat' );
 		parent::tearDown();
 	}
 
diff --git tests/phpunit/tests/query/dateQuery.php tests/phpunit/tests/query/dateQuery.php
index f40302d..7aadc8d 100644
--- tests/phpunit/tests/query/dateQuery.php
+++ tests/phpunit/tests/query/dateQuery.php
@@ -848,7 +848,7 @@ class Tests_Query_DateQuery extends WP_UnitTestCase {
 			),
 		) );
 
-		_unregister_taxonomy( 'foo' );
+		unregister_taxonomy( 'foo' );
 
 		$this->assertEquals( array( $p1 ), wp_list_pluck( $posts, 'ID' ) );
 	}
diff --git tests/phpunit/tests/query/isTerm.php tests/phpunit/tests/query/isTerm.php
index c9a4160..294b33d 100644
--- tests/phpunit/tests/query/isTerm.php
+++ tests/phpunit/tests/query/isTerm.php
@@ -58,7 +58,7 @@ class Tests_Query_IsTerm extends WP_UnitTestCase {
 	function tearDown() {
 		global $wp_rewrite;
 
-		_unregister_taxonomy( 'testtax' );
+		unregister_taxonomy( 'testtax' );
 
 		$wp_rewrite->init();
 
diff --git tests/phpunit/tests/query/taxQuery.php tests/phpunit/tests/query/taxQuery.php
index 8248b19..6265afa 100644
--- tests/phpunit/tests/query/taxQuery.php
+++ tests/phpunit/tests/query/taxQuery.php
@@ -691,8 +691,8 @@ class Tests_Query_TaxQuery extends WP_UnitTestCase {
 			),
 		) );
 
-		_unregister_taxonomy( 'foo' );
-		_unregister_taxonomy( 'bar' );
+		unregister_taxonomy( 'foo' );
+		unregister_taxonomy( 'bar' );
 
 		$this->assertEqualSets( array( $p1, $p2 ), $q->posts );
 	}
@@ -755,8 +755,8 @@ class Tests_Query_TaxQuery extends WP_UnitTestCase {
 			),
 		) );
 
-		_unregister_taxonomy( 'foo' );
-		_unregister_taxonomy( 'bar' );
+		unregister_taxonomy( 'foo' );
+		unregister_taxonomy( 'bar' );
 
 		$this->assertEqualSets( array( $p1, $p2 ), $q->posts );
 	}
@@ -828,8 +828,8 @@ class Tests_Query_TaxQuery extends WP_UnitTestCase {
 			),
 		) );
 
-		_unregister_taxonomy( 'foo' );
-		_unregister_taxonomy( 'bar' );
+		unregister_taxonomy( 'foo' );
+		unregister_taxonomy( 'bar' );
 
 		$this->assertEqualSets( array( $p1, $p2, $p3 ), $q->posts );
 	}
@@ -1185,7 +1185,7 @@ class Tests_Query_TaxQuery extends WP_UnitTestCase {
 
 		$this->assertSame( 'foo', $q->get( 'taxonomy' ) );
 
-		_unregister_taxonomy( 'foo' );
+		unregister_taxonomy( 'foo' );
 	}
 
 	public function test_populate_taxonomy_query_var_from_tax_query_taxonomy_already_set() {
@@ -1207,8 +1207,8 @@ class Tests_Query_TaxQuery extends WP_UnitTestCase {
 
 		$this->assertSame( 'bar', $q->get( 'taxonomy' ) );
 
-		_unregister_taxonomy( 'foo' );
-		_unregister_taxonomy( 'foo1' );
+		unregister_taxonomy( 'foo' );
+		unregister_taxonomy( 'foo1' );
 	}
 
 	public function test_populate_term_query_var_from_tax_query() {
@@ -1230,7 +1230,7 @@ class Tests_Query_TaxQuery extends WP_UnitTestCase {
 
 		$this->assertSame( 'bar', $q->get( 'term' ) );
 
-		_unregister_taxonomy( 'foo' );
+		unregister_taxonomy( 'foo' );
 	}
 
 	public function test_populate_term_id_query_var_from_tax_query() {
@@ -1252,7 +1252,7 @@ class Tests_Query_TaxQuery extends WP_UnitTestCase {
 
 		$this->assertEquals( $t, $q->get( 'term_id' ) );
 
-		_unregister_taxonomy( 'foo' );
+		unregister_taxonomy( 'foo' );
 	}
 
 	/**
@@ -1293,7 +1293,7 @@ class Tests_Query_TaxQuery extends WP_UnitTestCase {
 		$this->assertEquals( $c, $q->get( 'cat' ) );
 		$this->assertEquals( 'bar', $q->get( 'category_name' ) );
 
-		_unregister_taxonomy( 'foo' );
+		unregister_taxonomy( 'foo' );
 	}
 
 	/**
@@ -1333,6 +1333,6 @@ class Tests_Query_TaxQuery extends WP_UnitTestCase {
 
 		$this->assertEquals( $tag, $q->get( 'tag_id' ) );
 
-		_unregister_taxonomy( 'foo' );
+		unregister_taxonomy( 'foo' );
 	}
 }
diff --git tests/phpunit/tests/taxonomy.php tests/phpunit/tests/taxonomy.php
index 2063bbe..f4b68bc 100644
--- tests/phpunit/tests/taxonomy.php
+++ tests/phpunit/tests/taxonomy.php
@@ -235,7 +235,7 @@ class Tests_Taxonomy extends WP_UnitTestCase {
 		$this->assertFalse( unregister_taxonomy_for_object_type( $tax, 'user' ) );
 
 		unset($GLOBALS['wp_taxonomies'][$tax]);
-		_unregister_post_type( $post_type );
+		unregister_post_type( $post_type );
 
 	}
 
@@ -351,7 +351,7 @@ class Tests_Taxonomy extends WP_UnitTestCase {
 		) );
 
 		$this->assertSame( array(), get_ancestors( $t, 'wptests_tax' ) );
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 	}
 
 	public function test_get_ancestors_taxonomy() {
@@ -375,7 +375,7 @@ class Tests_Taxonomy extends WP_UnitTestCase {
 		) );
 
 		$this->assertEqualSets( array( $t2, $t1 ), get_ancestors( $t3, 'wptests_tax' ) );
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 	}
 
 	public function test_get_ancestors_post_type_non_hierarchical() {
@@ -408,7 +408,7 @@ class Tests_Taxonomy extends WP_UnitTestCase {
 		) );
 
 		$this->assertEqualSets( array( $p2, $p1 ), get_ancestors( $p3, 'wptests_pt' ) );
-		_unregister_post_type( 'wptests_pt' );
+		unregister_post_type( 'wptests_pt' );
 	}
 
 	/**
@@ -440,7 +440,7 @@ class Tests_Taxonomy extends WP_UnitTestCase {
 		$this->assertEqualSets( array( $p1 ), get_ancestors( $p2, 'wptests_conflict', 'post_type' ) );
 		$this->assertEqualSets( array( $t1 ), get_ancestors( $t2, 'wptests_conflict', 'taxonomy' ) );
 		$this->assertEqualSets( array( $t1 ), get_ancestors( $t2, 'wptests_conflict' ) );
-		_unregister_post_type( 'wptests_pt' );
+		unregister_post_type( 'wptests_pt' );
 	}
 
 	/**
@@ -517,4 +517,99 @@ class Tests_Taxonomy extends WP_UnitTestCase {
 
 		$this->assertFalse( is_tax( 'wptests_tax' ) );
 	}
+
+	/**
+	 * @ticket 35227
+	 */
+	public function test_unregister_taxonomy() {
+		register_taxonomy( 'foo', 'post' );
+		$this->assertTrue( unregister_taxonomy( 'foo' ) );
+	}
+
+	/**
+	 * @ticket 35227
+	 */
+	public function test_unregister_taxonomy_unknown_taxonomy() {
+		$this->assertFalse( unregister_taxonomy( 'foo' ) );
+	}
+
+	/**
+	 * @ticket 35227
+	 */
+	public function test_unregister_taxonomy_twice() {
+		register_taxonomy( 'foo', 'post' );
+		$this->assertTrue( unregister_taxonomy( 'foo' ) );
+		$this->assertFalse( unregister_taxonomy( 'foo' ) );
+	}
+
+	/**
+	 * @ticket 35227
+	 */
+	public function test_unregister_taxonomy_disallow_builtin_taxonomy() {
+		$this->assertFalse( unregister_taxonomy( 'post_tag' ) );
+		$this->assertFalse( unregister_taxonomy( 'category' ) );
+	}
+
+	/**
+	 * @ticket 35227
+	 */
+	public function test_unregister_taxonomy_removes_query_vars() {
+		global $wp;
+
+		register_taxonomy( 'foo', 'post', array( 'query_var' => 'bar' ) );
+
+		$this->assertInternalType( 'int', array_search( 'bar', $wp->public_query_vars ) );
+		$this->assertTrue( unregister_taxonomy( 'foo' ) );
+		$this->assertFalse( array_search( 'bar', $wp->public_query_vars ) );
+	}
+
+	/**
+	 * @ticket 35227
+	 */
+	public function test_unregister_taxonomy_removes_rewrite_rules() {
+		$this->set_permalink_structure( '/%postname%' );
+
+		global $wp_rewrite;
+
+		register_taxonomy( 'foo', 'post', array( 'query_var' => 'bar' ) );
+
+		$count_before = count( $wp_rewrite->rewritereplace );
+
+		$this->assertInternalType( 'int', array_search( '%foo%', $wp_rewrite->rewritecode ) );
+		$this->assertInternalType( 'int', array_search( 'bar=', $wp_rewrite->queryreplace ) );
+		$this->assertTrue( unregister_taxonomy( 'foo' ) );
+		$this->assertFalse( array_search( '%foo%', $wp_rewrite->rewritecode ) );
+		$this->assertFalse( array_search( 'bar=', $wp_rewrite->queryreplace ) );
+		$this->assertSame( --$count_before, count( $wp_rewrite->rewritereplace ) ); // Array was reduced by one value.
+	}
+
+	/**
+	 * @ticket 35227
+	 */
+	public function test_unregister_taxonomy_removes_taxonomy_from_global() {
+		global $wp_taxonomies;
+
+		register_taxonomy( 'foo', 'post' );
+
+		$this->assertInternalType( 'object', $wp_taxonomies['foo'] );
+		$this->assertInternalType( 'object', get_taxonomy( 'foo' ) );
+
+		$this->assertTrue( unregister_taxonomy( 'foo' ) );
+
+		$this->assertFalse( isset( $wp_taxonomies['foo'] ) );
+		$this->assertFalse( get_taxonomy( 'foo' ) );
+	}
+
+	/**
+	 * @ticket 35227
+	 */
+	public function test_unregister_taxonomy_removes_meta_box_callback() {
+		global $wp_filter;
+
+		register_taxonomy( 'foo', 'post' );
+
+		$this->assertSame( 1, count( $wp_filter['wp_ajax_add-foo'] ) );
+		$this->assertTrue( unregister_taxonomy( 'foo' ) );
+		$this->assertSame( array(), $wp_filter['wp_ajax_add-foo'] );
+	}
 }
diff --git tests/phpunit/tests/term.php tests/phpunit/tests/term.php
index 1fdbd14..d206431 100644
--- tests/phpunit/tests/term.php
+++ tests/phpunit/tests/term.php
@@ -243,7 +243,7 @@ class Tests_Term extends WP_UnitTestCase {
 		$this->assertNotEmpty( $added2 );
 		$this->assertEqualSets( array( $t1, $t2 ), wp_get_object_terms( $p, 'wptests_tax', array( 'fields' => 'ids' ) ) );
 
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 	}
 
 	public function test_wp_set_object_terms_append_false() {
@@ -264,7 +264,7 @@ class Tests_Term extends WP_UnitTestCase {
 		$this->assertNotEmpty( $added2 );
 		$this->assertEqualSets( array( $t2 ), wp_get_object_terms( $p, 'wptests_tax', array( 'fields' => 'ids' ) ) );
 
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 	}
 
 	public function test_wp_set_object_terms_append_default_to_false() {
@@ -285,7 +285,7 @@ class Tests_Term extends WP_UnitTestCase {
 		$this->assertNotEmpty( $added2 );
 		$this->assertEqualSets( array( $t2 ), wp_get_object_terms( $p, 'wptests_tax', array( 'fields' => 'ids' ) ) );
 
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 	}
 
 	function test_change_object_terms_by_id() {
diff --git tests/phpunit/tests/term/cache.php tests/phpunit/tests/term/cache.php
index 828917a..bf10fab 100644
--- tests/phpunit/tests/term/cache.php
+++ tests/phpunit/tests/term/cache.php
@@ -91,7 +91,7 @@ class Tests_Term_Cache extends WP_UnitTestCase {
 			}
 		}
 
-		_unregister_taxonomy( $tax );
+		unregister_taxonomy( $tax );
 	}
 
 	public function test_get_term_should_update_term_cache_when_passed_an_object() {
@@ -198,6 +198,6 @@ class Tests_Term_Cache extends WP_UnitTestCase {
 
 		$this->assertSame( $num_queries, $wpdb->num_queries );
 
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 	}
 }
diff --git tests/phpunit/tests/term/getTerm.php tests/phpunit/tests/term/getTerm.php
index 7aeb3f3..fac495e 100644
--- tests/phpunit/tests/term/getTerm.php
+++ tests/phpunit/tests/term/getTerm.php
@@ -211,7 +211,7 @@ class Tests_Term_GetTerm extends WP_UnitTestCase {
 	public function test_should_return_error_when_only_matching_term_is_in_an_invalid_taxonomy() {
 		$t = self::factory()->term->create( array( 'taxonomy' => 'wptests_tax' ) );
 
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 
 		$found = get_term( $t );
 		$this->assertWPError( $found );
@@ -224,7 +224,7 @@ class Tests_Term_GetTerm extends WP_UnitTestCase {
 	public function test_term_should_be_returned_when_id_is_shared_only_with_invalid_taxonomies() {
 		$terms = $this->generate_shared_terms();
 
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 
 		$found = get_term( $terms[1]['term_id'] );
 		$this->assertInstanceOf( 'WP_Term', $found );
diff --git tests/phpunit/tests/term/getTerms.php tests/phpunit/tests/term/getTerms.php
index bcd3485..d771aaa 100644
--- tests/phpunit/tests/term/getTerms.php
+++ tests/phpunit/tests/term/getTerms.php
@@ -192,7 +192,7 @@ class Tests_Term_getTerms extends WP_UnitTestCase {
 
 		$this->assertEquals( array( $terms[1] ), wp_list_pluck( $found, 'term_id' ) );
 
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 	}
 
 	/**
@@ -336,7 +336,7 @@ class Tests_Term_getTerms extends WP_UnitTestCase {
 		$this->assertEquals( 1, count( $terms ) );
 		$this->assertEquals( array( 'Cheese' ), wp_list_pluck( $terms, 'name' ) );
 
-		_unregister_taxonomy( $tax );
+		unregister_taxonomy( $tax );
 	}
 
 	/**
@@ -360,7 +360,7 @@ class Tests_Term_getTerms extends WP_UnitTestCase {
 		$this->assertEquals( 1, count( $terms ) );
 		$this->assertEquals( array( 'term1' ), wp_list_pluck( $terms, 'name' ) );
 
-		_unregister_taxonomy( $tax );
+		unregister_taxonomy( $tax );
 	}
 
 	/**
@@ -697,7 +697,7 @@ class Tests_Term_getTerms extends WP_UnitTestCase {
 			$terms['grandchild1'],
 		);
 
-		_unregister_taxonomy( 'hierarchical_fields' );
+		unregister_taxonomy( 'hierarchical_fields' );
 
 		$this->assertEqualSets( $expected, $found );
 	}
@@ -720,7 +720,7 @@ class Tests_Term_getTerms extends WP_UnitTestCase {
 			$terms['child1'],
 		);
 
-		_unregister_taxonomy( 'hierarchical_fields' );
+		unregister_taxonomy( 'hierarchical_fields' );
 
 		$this->assertEqualSets( $expected, $found );
 	}
@@ -743,7 +743,7 @@ class Tests_Term_getTerms extends WP_UnitTestCase {
 			$terms['child1'],
 		);
 
-		_unregister_taxonomy( 'hierarchical_fields' );
+		unregister_taxonomy( 'hierarchical_fields' );
 
 		$this->assertEqualSets( $expected, $found );
 	}
@@ -768,7 +768,7 @@ class Tests_Term_getTerms extends WP_UnitTestCase {
 			'Grandchild 1',
 		);
 
-		_unregister_taxonomy( 'hierarchical_fields' );
+		unregister_taxonomy( 'hierarchical_fields' );
 
 		$this->assertEqualSets( $expected, $found );
 	}
@@ -791,7 +791,7 @@ class Tests_Term_getTerms extends WP_UnitTestCase {
 			'Child 1',
 		);
 
-		_unregister_taxonomy( 'hierarchical_fields' );
+		unregister_taxonomy( 'hierarchical_fields' );
 
 		$this->assertEqualSets( $expected, $found );
 	}
@@ -814,7 +814,7 @@ class Tests_Term_getTerms extends WP_UnitTestCase {
 			'Child 1',
 		);
 
-		_unregister_taxonomy( 'hierarchical_fields' );
+		unregister_taxonomy( 'hierarchical_fields' );
 
 		$this->assertEqualSets( $expected, $found );
 	}
@@ -831,7 +831,7 @@ class Tests_Term_getTerms extends WP_UnitTestCase {
 			'fields' => 'count',
 		) );
 
-		_unregister_taxonomy( 'hierarchical_fields' );
+		unregister_taxonomy( 'hierarchical_fields' );
 
 		$this->assertEquals( 5, $found );
 	}
@@ -848,7 +848,7 @@ class Tests_Term_getTerms extends WP_UnitTestCase {
 			'fields' => 'count',
 		) );
 
-		_unregister_taxonomy( 'hierarchical_fields' );
+		unregister_taxonomy( 'hierarchical_fields' );
 
 		// When using 'fields=count', 'hierarchical' is forced to false.
 		$this->assertEquals( 2, $found );
@@ -867,7 +867,7 @@ class Tests_Term_getTerms extends WP_UnitTestCase {
 			'hierarchical' => false,
 		) );
 
-		_unregister_taxonomy( 'hierarchical_fields' );
+		unregister_taxonomy( 'hierarchical_fields' );
 
 		$this->assertEquals( 2, $found );
 	}
@@ -892,7 +892,7 @@ class Tests_Term_getTerms extends WP_UnitTestCase {
 			$terms['grandchild1'] => $terms['child1'],
 		);
 
-		_unregister_taxonomy( 'hierarchical_fields' );
+		unregister_taxonomy( 'hierarchical_fields' );
 
 		$this->assertEqualSetsWithIndex( $expected, $found );
 	}
@@ -915,7 +915,7 @@ class Tests_Term_getTerms extends WP_UnitTestCase {
 			$terms['child1'] => $terms['parent1'],
 		);
 
-		_unregister_taxonomy( 'hierarchical_fields' );
+		unregister_taxonomy( 'hierarchical_fields' );
 
 		$this->assertEqualSetsWithIndex( $expected, $found );
 	}
@@ -938,7 +938,7 @@ class Tests_Term_getTerms extends WP_UnitTestCase {
 			$terms['child1'] => $terms['parent1'],
 		);
 
-		_unregister_taxonomy( 'hierarchical_fields' );
+		unregister_taxonomy( 'hierarchical_fields' );
 
 		$this->assertEqualSetsWithIndex( $expected, $found );
 	}
@@ -963,7 +963,7 @@ class Tests_Term_getTerms extends WP_UnitTestCase {
 			$terms['grandchild1'] => 'grandchild-1',
 		);
 
-		_unregister_taxonomy( 'hierarchical_fields' );
+		unregister_taxonomy( 'hierarchical_fields' );
 
 		$this->assertEqualSetsWithIndex( $expected, $found );
 	}
@@ -989,7 +989,7 @@ class Tests_Term_getTerms extends WP_UnitTestCase {
 			$terms['child1'] => 'child-1',
 		);
 
-		_unregister_taxonomy( 'hierarchical_fields' );
+		unregister_taxonomy( 'hierarchical_fields' );
 
 		$this->assertEqualSetsWithIndex( $expected, $found );
 	}
@@ -1012,7 +1012,7 @@ class Tests_Term_getTerms extends WP_UnitTestCase {
 			$terms['child1'] => 'child-1',
 		);
 
-		_unregister_taxonomy( 'hierarchical_fields' );
+		unregister_taxonomy( 'hierarchical_fields' );
 
 		$this->assertEqualSetsWithIndex( $expected, $found );
 	}
@@ -1037,7 +1037,7 @@ class Tests_Term_getTerms extends WP_UnitTestCase {
 			$terms['grandchild1'] => 'Grandchild 1',
 		);
 
-		_unregister_taxonomy( 'hierarchical_fields' );
+		unregister_taxonomy( 'hierarchical_fields' );
 
 		$this->assertEqualSetsWithIndex( $expected, $found );
 	}
@@ -1063,7 +1063,7 @@ class Tests_Term_getTerms extends WP_UnitTestCase {
 			$terms['child1'] => 'Child 1',
 		);
 
-		_unregister_taxonomy( 'hierarchical_fields' );
+		unregister_taxonomy( 'hierarchical_fields' );
 
 		$this->assertEqualSetsWithIndex( $expected, $found );
 	}
@@ -1086,7 +1086,7 @@ class Tests_Term_getTerms extends WP_UnitTestCase {
 			$terms['child1'] => 'Child 1',
 		);
 
-		_unregister_taxonomy( 'hierarchical_fields' );
+		unregister_taxonomy( 'hierarchical_fields' );
 
 		$this->assertEqualSetsWithIndex( $expected, $found );
 	}
@@ -1152,7 +1152,7 @@ class Tests_Term_getTerms extends WP_UnitTestCase {
 			'hide_empty' => false,
 		) );
 
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 
 		$this->assertEquals( array( $t4, $t1, $t2 ), $found );
 	}
@@ -1175,7 +1175,7 @@ class Tests_Term_getTerms extends WP_UnitTestCase {
 			'hide_empty' => false,
 		) );
 
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 
 		$this->assertEquals( array( $t2, $t1, $t4, $t3 ), $found );
 	}
diff --git tests/phpunit/tests/term/isObjectInTerm.php tests/phpunit/tests/term/isObjectInTerm.php
index 0da95ab..ef8a87c 100644
--- tests/phpunit/tests/term/isObjectInTerm.php
+++ tests/phpunit/tests/term/isObjectInTerm.php
@@ -16,7 +16,7 @@ class Tests_IsObjectInTerm extends WP_UnitTestCase {
 		$this->assertTrue( is_object_in_term( $posts[0], 'wptests_tax', array( $t1, $t2 ) ) );
 		$this->assertFalse( is_object_in_term( $posts[1], 'wptests_tax', array( $t1, $t2 ) ) );
 
-		_unregister_taxonomy( 'wptests_tax', 'post' );
+		unregister_taxonomy( 'wptests_tax', 'post' );
 	}
 
 	public function test_terms_are_strings_and_match_term_id() {
@@ -34,7 +34,7 @@ class Tests_IsObjectInTerm extends WP_UnitTestCase {
 		$this->assertTrue( is_object_in_term( $posts[0], 'wptests_tax', array( $t1_str, $t2_str ) ) );
 		$this->assertFalse( is_object_in_term( $posts[1], 'wptests_tax', array( $t1_str, $t2_str ) ) );
 
-		_unregister_taxonomy( 'wptests_tax', 'post' );
+		unregister_taxonomy( 'wptests_tax', 'post' );
 	}
 
 	public function test_terms_are_strings_and_match_term_name() {
@@ -49,7 +49,7 @@ class Tests_IsObjectInTerm extends WP_UnitTestCase {
 		$this->assertTrue( is_object_in_term( $posts[0], 'wptests_tax', array( 'Foo', 'Bar' ) ) );
 		$this->assertFalse( is_object_in_term( $posts[1], 'wptests_tax', array( 'Foo', 'Bar' ) ) );
 
-		_unregister_taxonomy( 'wptests_tax', 'post' );
+		unregister_taxonomy( 'wptests_tax', 'post' );
 	}
 
 	public function test_terms_are_strings_and_match_term_slug() {
@@ -64,7 +64,7 @@ class Tests_IsObjectInTerm extends WP_UnitTestCase {
 		$this->assertTrue( is_object_in_term( $posts[0], 'wptests_tax', array( 'foo', 'bar' ) ) );
 		$this->assertFalse( is_object_in_term( $posts[1], 'wptests_tax', array( 'foo', 'bar' ) ) );
 
-		_unregister_taxonomy( 'wptests_tax', 'post' );
+		unregister_taxonomy( 'wptests_tax', 'post' );
 	}
 
 	public function test_terms_contain_strings_and_ints_and_match_term_id_as_int() {
@@ -79,7 +79,7 @@ class Tests_IsObjectInTerm extends WP_UnitTestCase {
 		$this->assertTrue( is_object_in_term( $posts[0], 'wptests_tax', array( $t1, 'bar' ) ) );
 		$this->assertFalse( is_object_in_term( $posts[1], 'wptests_tax', array( $t1, 'bar' ) ) );
 
-		_unregister_taxonomy( 'wptests_tax', 'post' );
+		unregister_taxonomy( 'wptests_tax', 'post' );
 	}
 
 	/**
diff --git tests/phpunit/tests/term/query.php tests/phpunit/tests/term/query.php
index 2b717c7..597d964 100644
--- tests/phpunit/tests/term/query.php
+++ tests/phpunit/tests/term/query.php
@@ -275,7 +275,7 @@ class Tests_Tax_Query extends WP_UnitTestCase {
 		// Only one JOIN is required with OR + IN.
 		$this->assertSame( 1, substr_count( $sql['join'], 'JOIN' ) );
 
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 	}
 
 	/**
@@ -318,7 +318,7 @@ class Tests_Tax_Query extends WP_UnitTestCase {
 
 		$this->assertSame( 3, substr_count( $sql['join'], 'JOIN' ) );
 
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 	}
 
 	/**
@@ -364,7 +364,7 @@ class Tests_Tax_Query extends WP_UnitTestCase {
 
 		$this->assertSame( 2, substr_count( $sql['join'], 'JOIN' ) );
 
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 	}
 
 	/**
@@ -391,7 +391,7 @@ class Tests_Tax_Query extends WP_UnitTestCase {
 
 		$this->assertSame( $expected, $tq->get_sql( $wpdb->posts, 'ID' ) );
 
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 	}
 
 	/**
@@ -418,6 +418,6 @@ class Tests_Tax_Query extends WP_UnitTestCase {
 
 		$this->assertSame( $expected, $tq->get_sql( $wpdb->posts, 'ID' ) );
 
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 	}
 }
diff --git tests/phpunit/tests/term/termExists.php tests/phpunit/tests/term/termExists.php
index b00b6e8..5c8e71e 100644
--- tests/phpunit/tests/term/termExists.php
+++ tests/phpunit/tests/term/termExists.php
@@ -96,7 +96,7 @@ class Tests_TermExists extends WP_UnitTestCase {
 
 		$found = term_exists( 'child-term', 'foo', $parent_term );
 
-		_unregister_taxonomy( 'foo' );
+		unregister_taxonomy( 'foo' );
 
 		$this->assertInternalType( 'array', $found );
 		$this->assertEquals( $t, $found['term_id'] );
@@ -122,7 +122,7 @@ class Tests_TermExists extends WP_UnitTestCase {
 
 		$found = term_exists( 'child-term', 'foo', 0 );
 
-		_unregister_taxonomy( 'foo' );
+		unregister_taxonomy( 'foo' );
 
 		$this->assertSame( null, $found['term_id'] );
 	}
@@ -144,7 +144,7 @@ class Tests_TermExists extends WP_UnitTestCase {
 
 		$found = term_exists( 'Child Term', 'foo', $parent_term );
 
-		_unregister_taxonomy( 'foo' );
+		unregister_taxonomy( 'foo' );
 
 		$this->assertInternalType( 'array', $found );
 		$this->assertEquals( $t, $found['term_id'] );
@@ -160,7 +160,7 @@ class Tests_TermExists extends WP_UnitTestCase {
 
 		$found = term_exists( 'kewl-dudez', 'foo' );
 
-		_unregister_taxonomy( 'foo' );
+		unregister_taxonomy( 'foo' );
 
 		$this->assertInternalType( 'array', $found );
 		$this->assertEquals( $t, $found['term_id'] );
@@ -176,7 +176,7 @@ class Tests_TermExists extends WP_UnitTestCase {
 
 		$found = term_exists( 'Kewl Dudez', 'foo' );
 
-		_unregister_taxonomy( 'foo' );
+		unregister_taxonomy( 'foo' );
 
 		$this->assertInternalType( 'array', $found );
 		$this->assertEquals( $t, $found['term_id'] );
@@ -192,7 +192,7 @@ class Tests_TermExists extends WP_UnitTestCase {
 
 		$found = term_exists( 'juicy-fruit' );
 
-		_unregister_taxonomy( 'foo' );
+		unregister_taxonomy( 'foo' );
 
 		$this->assertInternalType( 'string', $found );
 		$this->assertEquals( $t, $found );
@@ -208,7 +208,7 @@ class Tests_TermExists extends WP_UnitTestCase {
 
 		$found = term_exists( 'Juicy Fruit' );
 
-		_unregister_taxonomy( 'foo' );
+		unregister_taxonomy( 'foo' );
 
 		$this->assertInternalType( 'string', $found );
 		$this->assertEquals( $t, $found );
@@ -226,7 +226,7 @@ class Tests_TermExists extends WP_UnitTestCase {
 
 		// clean up
 		$this->assertTrue( wp_delete_term( $t['term_id'], 'wptests_tax' ) );
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 	}
 
 	function test_term_exists_unknown() {
diff --git tests/phpunit/tests/term/wpInsertTerm.php tests/phpunit/tests/term/wpInsertTerm.php
index c3dea31..633dd48 100644
--- tests/phpunit/tests/term/wpInsertTerm.php
+++ tests/phpunit/tests/term/wpInsertTerm.php
@@ -89,7 +89,7 @@ class Tests_Term_WpInsertTerm extends WP_UnitTestCase {
 		$found = wp_insert_term( 'Let\\\'s all say \\"Hooray\\" for WordPress taxonomy', 'wptests_tax' );
 
 		$term = get_term( $found['term_id'], 'wptests_tax' );
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 
 		$this->assertSame( 'Let\'s all say "Hooray" for WordPress taxonomy', $term->name );
 	}
@@ -101,7 +101,7 @@ class Tests_Term_WpInsertTerm extends WP_UnitTestCase {
 		) );
 
 		$term = get_term( $found['term_id'], 'wptests_tax' );
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 
 		$this->assertSame( 'Let\'s all say "Hooray" for WordPress taxonomy', $term->description );
 	}
@@ -113,7 +113,7 @@ class Tests_Term_WpInsertTerm extends WP_UnitTestCase {
 		) );
 
 		$term = get_term( $found['term_id'], 'wptests_tax' );
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 
 		// 'foo1' is cast to 0 in sanitize_term().
 		$this->assertSame( 0, $term->parent );
@@ -126,7 +126,7 @@ class Tests_Term_WpInsertTerm extends WP_UnitTestCase {
 		) );
 
 		$term = get_term( $found['term_id'], 'wptests_tax' );
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 
 		$this->assertSame( 'quality', $term->slug );
 
@@ -139,7 +139,7 @@ class Tests_Term_WpInsertTerm extends WP_UnitTestCase {
 		) );
 
 		$term = get_term( $found['term_id'], 'wptests_tax' );
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 
 		$this->assertSame( 'quality', $term->slug );
 	}
@@ -151,7 +151,7 @@ class Tests_Term_WpInsertTerm extends WP_UnitTestCase {
 		) );
 
 		$term = get_term( $found['term_id'], 'wptests_tax' );
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 
 		$this->assertSame( 'quality', $term->slug );
 	}
@@ -434,7 +434,7 @@ class Tests_Term_WpInsertTerm extends WP_UnitTestCase {
 		$created_term = get_term( $created['term_id'], 'wptests_tax' );
 		$this->assertSame( 'foo-2', $created_term->slug );
 
-		_unregister_taxonomy( 'wptests_tax', 'post' );
+		unregister_taxonomy( 'wptests_tax', 'post' );
 	}
 
 	/**
@@ -461,7 +461,7 @@ class Tests_Term_WpInsertTerm extends WP_UnitTestCase {
 
 		$this->assertSame( 'foo', $new_term->slug );
 
-		_unregister_taxonomy( 'wptests_tax', 'post' );
+		unregister_taxonomy( 'wptests_tax', 'post' );
 	}
 
 	/**
@@ -496,7 +496,7 @@ class Tests_Term_WpInsertTerm extends WP_UnitTestCase {
 		$this->assertSame( 'foo-2', $new_term->slug );
 		$this->assertNotEquals( $new_term->term_id, $term->term_id );
 
-		_unregister_taxonomy( 'wptests_tax', 'post' );
+		unregister_taxonomy( 'wptests_tax', 'post' );
 	}
 
 	public function test_wp_insert_term_alias_of_no_term_group() {
@@ -514,7 +514,7 @@ class Tests_Term_WpInsertTerm extends WP_UnitTestCase {
 		$updated_term_1 = get_term( $term_1->term_id, 'wptests_tax' );
 
 		$term = get_term( $created_term_ids['term_id'], 'wptests_tax' );
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 
 		$this->assertSame( 0, $term_1->term_group );
 		$this->assertNotEmpty( $created_term->term_group );
@@ -538,7 +538,7 @@ class Tests_Term_WpInsertTerm extends WP_UnitTestCase {
 			'alias_of' => $term_2->slug,
 		) );
 		$created_term = get_term( $created_term_ids['term_id'], 'wptests_tax' );
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 
 		$this->assertNotEmpty( $created_term->term_group );
 		$this->assertSame( $created_term->term_group, $term_2->term_group );
@@ -550,7 +550,7 @@ class Tests_Term_WpInsertTerm extends WP_UnitTestCase {
 			'alias_of' => 'foo',
 		) );
 		$created_term = get_term( $created_term_ids['term_id'], 'wptests_tax' );
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 
 		$this->assertSame( 0, $created_term->term_group );
 	}
@@ -576,7 +576,7 @@ class Tests_Term_WpInsertTerm extends WP_UnitTestCase {
 		$term_by_slug = get_term_by( 'slug', 'foo', 'wptests_tax' );
 		$term_by_ttid = get_term_by( 'term_taxonomy_id', $found['term_taxonomy_id'], 'wptests_tax' );
 
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 
 		$this->assertInternalType( 'array', $found );
 		$this->assertNotEmpty( $found['term_id'] );
@@ -607,7 +607,7 @@ class Tests_Term_WpInsertTerm extends WP_UnitTestCase {
 		$found = wp_insert_term( 'foo', 'wptests_tax', array(
 			'parent' => $t,
 		) );
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 
 		$this->assertSame( false, wp_cache_get( 'all_ids', 'wptests_tax' ) );
 		$this->assertSame( false, wp_cache_get( 'get', 'wptests_tax' ) );
diff --git tests/phpunit/tests/term/wpUpdateTerm.php tests/phpunit/tests/term/wpUpdateTerm.php
index 4d9d17b..f7eea70 100644
--- tests/phpunit/tests/term/wpUpdateTerm.php
+++ tests/phpunit/tests/term/wpUpdateTerm.php
@@ -29,7 +29,7 @@ class Tests_Term_WpUpdateTerm extends WP_UnitTestCase {
 		) );
 
 		$term = get_term( $found['term_id'], 'wptests_tax' );
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 
 		$this->assertSame( 'Let\'s all say "Hooray" for WordPress taxonomy', $term->name );
 	}
@@ -45,7 +45,7 @@ class Tests_Term_WpUpdateTerm extends WP_UnitTestCase {
 		) );
 
 		$term = get_term( $found['term_id'], 'wptests_tax' );
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 
 		$this->assertSame( 'Let\'s all say "Hooray" for WordPress taxonomy', $term->description );
 	}
@@ -62,7 +62,7 @@ class Tests_Term_WpUpdateTerm extends WP_UnitTestCase {
 
 		$this->assertTrue( is_wp_error( $found ) );
 		$this->assertSame( 'empty_term_name', $found->get_error_code() );
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 	}
 
 	/**
@@ -89,7 +89,7 @@ class Tests_Term_WpUpdateTerm extends WP_UnitTestCase {
 
 		$term = get_term( $t, 'wptests_tax' );
 		$this->assertEquals( 0, $term->parent );
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 	}
 
 	public function test_wp_update_term_slug_empty_string_while_not_updating_name() {
@@ -105,7 +105,7 @@ class Tests_Term_WpUpdateTerm extends WP_UnitTestCase {
 
 		$term = get_term( $t, 'wptests_tax' );
 		$this->assertSame( 'foo-bar', $term->slug );
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 	}
 
 	public function test_wp_update_term_slug_empty_string_while_updating_name() {
@@ -121,7 +121,7 @@ class Tests_Term_WpUpdateTerm extends WP_UnitTestCase {
 
 		$term = get_term( $t, 'wptests_tax' );
 		$this->assertSame( 'foo-bar', $term->slug );
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 	}
 
 	public function test_wp_update_term_slug_set_slug() {
@@ -136,7 +136,7 @@ class Tests_Term_WpUpdateTerm extends WP_UnitTestCase {
 
 		$term = get_term( $t, 'wptests_tax' );
 		$this->assertSame( 'foo-bar', $term->slug );
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 	}
 
 	/**
@@ -314,7 +314,7 @@ class Tests_Term_WpUpdateTerm extends WP_UnitTestCase {
 		$created_term = get_term( $created_term_ids['term_id'], 'wptests_tax' );
 
 		$updated_term_1 = get_term( $t1, 'wptests_tax' );
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 
 		$this->assertSame( 0, $term_1->term_group );
 		$this->assertNotEmpty( $created_term->term_group );
@@ -339,7 +339,7 @@ class Tests_Term_WpUpdateTerm extends WP_UnitTestCase {
 			'alias_of' => $term_2->slug,
 		) );
 		$created_term = get_term( $created_term_ids['term_id'], 'wptests_tax' );
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 
 		$this->assertNotEmpty( $created_term->term_group );
 		$this->assertSame( $created_term->term_group, $term_2->term_group );
@@ -352,7 +352,7 @@ class Tests_Term_WpUpdateTerm extends WP_UnitTestCase {
 			'alias_of' => 'bar',
 		) );
 		$created_term = get_term( $created_term_ids['term_id'], 'wptests_tax' );
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 
 		$this->assertSame( 0, $created_term->term_group );
 	}
@@ -372,7 +372,7 @@ class Tests_Term_WpUpdateTerm extends WP_UnitTestCase {
 
 		$this->assertSame( $t, $found['term_id'] );
 		$this->assertSame( 'foo', $term->slug );
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 	}
 
 	public function test_wp_update_term_duplicate_slug_generated_due_to_empty_slug_param() {
@@ -395,7 +395,7 @@ class Tests_Term_WpUpdateTerm extends WP_UnitTestCase {
 
 		$this->assertSame( $t2, $found['term_id'] );
 		$this->assertSame( 'foo-bar-2', $term->slug );
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 	}
 
 	public function test_wp_update_term_duplicate_slug_with_changed_parent() {
@@ -423,7 +423,7 @@ class Tests_Term_WpUpdateTerm extends WP_UnitTestCase {
 
 		$this->assertSame( $t2, $found['term_id'] );
 		$this->assertSame( 'foo-bar-' . $parent_term->slug, $term->slug );
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 	}
 
 	public function test_wp_update_term_duplicate_slug_failure() {
@@ -446,7 +446,7 @@ class Tests_Term_WpUpdateTerm extends WP_UnitTestCase {
 		$this->assertWPError( $found );
 		$this->assertSame( 'duplicate_term_slug', $found->get_error_code() );
 		$this->assertSame( 'my-old-slug', $term->slug );
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 	}
 
 	public function test_wp_update_term_should_return_term_id_and_term_taxonomy_id() {
@@ -462,7 +462,7 @@ class Tests_Term_WpUpdateTerm extends WP_UnitTestCase {
 		$term_by_slug = get_term_by( 'slug', 'foo', 'wptests_tax' );
 		$term_by_ttid = get_term_by( 'term_taxonomy_id', $found['term_taxonomy_id'], 'wptests_tax' );
 
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 
 		$this->assertInternalType( 'array', $found );
 		$this->assertNotEmpty( $found['term_id'] );
@@ -546,7 +546,7 @@ class Tests_Term_WpUpdateTerm extends WP_UnitTestCase {
 		$found = wp_update_term( $t1, 'wptests_tax', array(
 			'parent' => $t2,
 		) );
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 
 		$this->assertSame( false, wp_cache_get( 'all_ids', 'wptests_tax' ) );
 		$this->assertSame( false, wp_cache_get( 'get', 'wptests_tax' ) );
@@ -585,7 +585,7 @@ class Tests_Term_WpUpdateTerm extends WP_UnitTestCase {
 
 		$this->assertSame( 'foo', $t2_term->slug );
 
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 	}
 
 	/**
@@ -623,7 +623,7 @@ class Tests_Term_WpUpdateTerm extends WP_UnitTestCase {
 
 		$this->assertSame( 'foo', $t3_term->slug );
 
-		_unregister_taxonomy( 'wptests_tax' );
+		unregister_taxonomy( 'wptests_tax' );
 	}
 
 	/**