automatic(redirected from on automatic)
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a. (of a device, mechanism, etc.) able to activate, move, or regulate itself
b. (of an act or process) performed by such automatic equipment
2. (of the action of a muscle, gland, etc.) involuntary or reflex
3. a motor vehicle having automatic transmission
4. a machine that operates automatically
Having a self-acting mechanism that performs a required act at a predetermined time or in response to certain conditions.
Said of a door, window, or other opening protective device that is so constructed and arranged that, when actuated by a predetermined temperature or rise in temperature, it will operate as intended.