Source

File: wp-includes/class-wp-rewrite.php

public function remove_rewrite_tag( $tag ) {
		$position = array_search( $tag, $this->rewritecode, true );
		if ( false !== $position && null !== $position ) {
			unset( $this->rewritecode[ $position ] );
			unset( $this->rewritereplace[ $position ] );
			unset( $this->queryreplace[ $position ] );
		}
	}