delete_metadata_by_mid( string $meta_type, int $meta_id )

function delete_metadata_by_mid( $meta_type, $meta_id ) {
    global $wpdb;

    // Make sure everything is valid.
    if ( ! $meta_type || ! is_numeric( $meta_id ) || floor( $meta_id ) != $meta_id ) {
        return false;
    }

    $meta_id = (int) $meta_id;
    if ( $meta_id <= 0 ) {
        return false;
    }

    $table = _get_meta_table( $meta_type );
    if ( ! $table ) {
        return false;
    }

    // Object and ID columns.
    $column    = sanitize_key( $meta_type . '_id' );
    $id_column = ( 'user' === $meta_type ) ? 'umeta_id' : 'meta_id';

    /**
     * Short-circuits deleting metadata of a specific type by meta ID.
     *
     * The dynamic portion of the hook name, `$meta_type`, refers to the meta object type
     * (post, comment, term, user, or any other type with an associated meta table).
     * Returning a non-null value will effectively short-circuit the function.
     *
     * Possible hook names include:
     *
     *  - `delete_post_metadata_by_mid`
     *  - `delete_comment_metadata_by_mid`
     *  - `delete_term_metadata_by_mid`
     *  - `delete_user_metadata_by_mid`
     *
     * @since 5.0.0
     *
     * @param null|bool $delete  Whether to allow metadata deletion of the given type.
     * @param int       $meta_id Meta ID.
     */
    $check = apply_filters( "delete_{$meta_type}_metadata_by_mid", null, $meta_id );
    if ( null !== $check ) {
        return (bool) $check;
    }

    // Fetch the meta and go on if it's found.
    $meta = get_metadata_by_mid( $meta_type, $meta_id );
    if ( $meta ) {
        $object_id = (int) $meta->{$column};

        /** This action is documented in wp-includes/meta.php */
        do_action( "delete_{$meta_type}_meta", (array) $meta_id, $object_id, $meta->meta_key, $meta->meta_value );

        // Old-style action.
        if ( 'post' === $meta_type || 'comment' === $meta_type ) {
            /**
             * Fires immediately before deleting post or comment metadata of a specific type.
             *
             * The dynamic portion of the hook name, `$meta_type`, refers to the meta
             * object type (post or comment).
             *
             * Possible hook names include:
             *
             *  - `delete_postmeta`
             *  - `delete_commentmeta`
             *  - `delete_termmeta`
             *  - `delete_usermeta`
             *
             * @since 3.4.0
             *
             * @param int $meta_id ID of the metadata entry to delete.
             */
            do_action( "delete_{$meta_type}meta", $meta_id );
        }

        // Run the query, will return true if deleted, false otherwise.
        $result = (bool) $wpdb->delete( $table, array( $id_column => $meta_id ) );

        // Clear the caches.
        wp_cache_delete( $object_id, $meta_type . '_meta' );

        /** This action is documented in wp-includes/meta.php */
        do_action( "deleted_{$meta_type}_meta", (array) $meta_id, $object_id, $meta->meta_key, $meta->meta_value );

        // Old-style action.
        if ( 'post' === $meta_type || 'comment' === $meta_type ) {
            /**
             * Fires immediately after deleting post or comment metadata of a specific type.
             *
             * The dynamic portion of the hook name, `$meta_type`, refers to the meta
             * object type (post or comment).
             *
             * Possible hook names include:
             *
             *  - `deleted_postmeta`
             *  - `deleted_commentmeta`
             *  - `deleted_termmeta`
             *  - `deleted_usermeta`
             *
             * @since 3.4.0
             *
             * @param int $meta_id Deleted metadata entry ID.
             */
            do_action( "deleted_{$meta_type}meta", $meta_id );
        }

        return $result;

    }

    // Meta ID was not found.
    return false;
}