the process or state of acting or of being active: The machine is not in action now.
2. something done or performed; act; deed.
3. an act that one consciously wills and that may be characterized by physical or mental activity: a crisis that demands action instead of debate; hoping for constructive action by the landlord.
4. actions, habitual or usual acts; conduct: He is responsible for his actions.
5. energetic activity: a man of action.
6. an exertion of power or force: the action of wind upon a ship's sails.
7. effect or influence: the action of morphine.
9. way or manner of moving: the action of a machine or of a horse.
10. the mechanism by which something is operated, as that of a gun or a piano.
11. a military encounter or engagement; battle, skirmish, or the like.
12. actual engagement in fighting an enemy; military or naval combat: He saw action in Vietnam.