$tax_query = array( array( 'taxonomy' => 'level', 'terms' => 'k-8', 'field' => 'slug', ), array( 'taxonomy' => 'season', 'terms' => 'season-one', 'field' => 'slug', ), array( 'taxonomy' => 'level', 'terms' => 'vacation-week', 'field' => 'slug', 'operator' => 'NOT IN', 'include_children' => true, ), );