diff --git src/wp-includes/class-wp-meta-query.php src/wp-includes/class-wp-meta-query.php
index d9234c2..4f76bf1 100644
--- src/wp-includes/class-wp-meta-query.php
+++ src/wp-includes/class-wp-meta-query.php
@@ -99,7 +99,8 @@ class WP_Meta_Query {
 	 *
 	 * @since 3.2.0
 	 * @since 4.2.0 Introduced support for naming query clauses by associative array keys.
-	 * @since 5.0.0 Introduced $compare_key clause parameter, which enables LIKE key matches.
+	 * @since 5.0.0 Introduced $compare_key clause parameter, which enables various key matches.
+	 * @since 5.0.0 Introduced $type_key clause parameter, which enables key casts.
 	 *
 	 * @param array $meta_query {
 	 *     Array of meta query clauses. When first-order clauses or sub-clauses use strings as
@@ -111,8 +112,13 @@ class WP_Meta_Query {
 	 *         Optional. An array of first-order clause parameters, or another fully-formed meta query.
 	 *
 	 *         @type string $key         Meta key to filter by.
-	 *         @type string $compare_key MySQL operator used for comparing the $key. Accepts '=' and 'LIKE'.
-	 *                                   Default '='.
+	 *         @type string $compare_key MySQL operator used for comparing the $key. Accepts '=' and '!='
+	 *                                   'LIKE', 'NOT LIKE', 'IN', 'NOT IN', 'REGEXP', 'NOT REGEXP', 'RLIKE',
+	 *                                   'EXISTS' or 'NOT EXISTS'.
+	 *                                   Default is 'IN' when `$key` is an array, '=' otherwise.
+	 *         @type string $type_key    MySQL data type that the meta_key column will be CAST to for
+	 *                                   comparisons. Accepts 'BINARY' for regular expression comparisons.
+	 *                                   Default is '' for case-insensitive REGEXP comparisons.
 	 *         @type string $value       Meta value to filter by.
 	 *         @type string $compare     MySQL operator used for comparing the $value. Accepts '=',
 	 *                                   '!=', '>', '>=', '<', '<=', 'LIKE', 'NOT LIKE',
diff --git src/wp-includes/class-wp-query.php src/wp-includes/class-wp-query.php
index b65ac1c..740a3dc 100644
--- src/wp-includes/class-wp-query.php
+++ src/wp-includes/class-wp-query.php
@@ -605,6 +605,7 @@ class WP_Query {
 	 * @since 4.6.0 Added 'post_name__in' support for `$orderby`. Introduced the `$lazy_load_term_meta` argument.
 	 * @since 4.9.0 Introduced the `$comment_count` parameter.
 	 * @since 5.0.0 Introduced the `$meta_compare_key` parameter.
+	 * @since 5.0.0 Introduced the `$meta_type_key` parameter.
 	 *
 	 * @param string|array $query {
 	 *     Optional. Array or string of Query parameters.
@@ -646,6 +647,7 @@ class WP_Query {
 	 *     @type array        $meta_query              An associative array of WP_Meta_Query arguments. See WP_Meta_Query.
 	 *     @type string       $meta_value              Custom field value.
 	 *     @type int          $meta_value_num          Custom field value number.
+	 *     @type string       $meta_type_key           Cast for 'meta_key'.
 	 *     @type int          $menu_order              The menu order of the posts.
 	 *     @type int          $monthnum                The two-digit month. Default empty. Accepts numbers 1-12.
 	 *     @type string       $name                    Post slug.