Hide product categories

add_filter( 'get_terms', 'ts_get_subcategory_terms', 10, 3 );

function ts_get_subcategory_terms( $terms, $taxonomies, $args ) {

$new_terms = array();

if ( in_array( 'product_cat', $taxonomies ) && ! is_admin() &&is_shop() ) {

foreach( $terms as $key => $term ) {

if ( !in_array( $term->slug, array( 'promo' ) ) ) { //pass the slug name here

$new_terms[] = $term;

}}

$terms = $new_terms;

}

return $terms;

}