1. To restore a storage device, memory device, or binary stage to a prescribed state, usually that denoting zero. Also known as reset.

2. A function key on calculators, to delete an entire problem or just the last keyboard entry.

1. After United States weather observing practice, the state of the sky when it is cloudless or when the sky cover is less than 0.1 (to the nearest tenth).

2. To change from a stormy or cloudy weather condition to one of no precipitation and decreased cloudiness.

In marine navigation, to leave or pass safely, as to clear port or clear a shoal.

1. To give a person a security clearance.

2. To operate a gun so as to unload it or make certain no ammunition remains; to free a gun of stoppages.