If something turns clockwise, it turns the same way the hands of a clock move: from the top toward the right, then down, then left, and back up. People use it for screws, taps, knobs, lids, and for moving around a circle ('start here and go clockwise'). You can say turn it clockwise, or a clockwise turn. It is a clear, practical word, not a fancy one. The opposite is counterclockwise in American English and anticlockwise in British English. In real life the direction is tidy; the feeling is not always. A 'righty-tighty' screw goes clockwise on a normal thread, but not every cap or valve follows that, so people still get caught.