WordPress at a glance
function is not described

update_term_cache() WP 2.3.0

Updates Terms to Taxonomy in cache.

No Hooks.

Return

Nothing (null).

Usage

update_term_cache( $terms, $taxonomy );
$terms(array) (required)
List of term objects to change.
$taxonomy(string)
Update Term to this taxonomy in cache.
Default: ''

Code of update term cache: wp-includes/taxonomy.php WP 5.2.2

<?php
function update_term_cache( $terms, $taxonomy = '' ) {
	foreach ( (array) $terms as $term ) {
		// Create a copy in case the array was passed by reference.
		$_term = clone $term;

		// Object ID should not be cached.
		unset( $_term->object_id );

		wp_cache_add( $term->term_id, $_term, 'terms' );
	}
}