A clockwise motion is one that procees 'like the clock's hands': from the top to the right, then down and then to the left, and back to the top. In a mathematical sense, a circle defined parametrically in a positive Cartesian plane by the equations x = sin t and y = cos t is traced clockwise as t increases in value. Another way to describe this motion is, relative to above you, clockwise is the motion you make when you constantly turn right. The opposite sense of rotation is anticlockwise (the current British English term), or counterclockwise (now chiefly North American English).