WordPress at a glance
function is not described

delete_site_meta_by_key() WP 5.1.0

Deletes everything from site meta matching meta key.

No Hooks.

Return

true/false. Whether the site meta key was deleted from the database.

Usage

delete_site_meta_by_key( $meta_key );
$meta_key(string) (required)
Metadata key to search for when deleting.

Changelog

Since 5.1.0 Introduced.

Code of delete_site_meta_by_key() WP 5.5.1

<?php
function delete_site_meta_by_key( $meta_key ) {
	return delete_metadata( 'blog', null, $meta_key, '', true );
}