Is the only way to add taxonomy terms via an admin panel?
I think you are looking for wp_insert_term(). An example from the Codex: $parent_term = term_exists( ‘fruits’, ‘product’ ); // array is returned if taxonomy is given $parent_term_id = $parent_term[‘term_id’]; // get numeric term id wp_insert_term( ‘Apple’, // the term ‘product’, // the taxonomy array( ‘description’=> ‘A yummy apple.’, ‘slug’ => ‘apple’, ‘parent’=> $parent_term_id ) );