Clockwise and Counterclockwise

Clockwise

Clockwise means moving in the direction of the hands on a clock.

Faucets (taps) are closed, and most screws and bolts are tightened, by turning clockwise.

Counterclockwise / Anticlockwise

The opposite direction is called counterclockwise in the US (or anticlockwise in the UK).

Angles from a line are measured counterclockwise (and a negative angle goes clockwise):

Abbreviation

Such long words deserve to be shortened.

So clockwise can be shortened to CW.

And counterclockwise to CCW (or maybe ACW for anticlockwise).