(with reference to a lid or other object held in place by a spiral thread) unfasten or be unfastened by twisting: [with object]:Will unscrewed the cap from a metal flask [no object]:the spout usually unscrews or lifts off easily
[with object] detach, open, or slacken (something) by removing or loosening the screws holding it in place:he unscrewed the number plates from his old Renault