adj. 1. a. Acting or operating in a manner essentially independent of external influence or control: an automatic light switch; a budget deficit that triggered automatic spending cuts. b. Self-regulating: an automatic washing machine. 2. a. Acting or done without volition or conscious control; involuntary: automatic shrinking of the pupils of the eyes in strong light. b. Acting or done as if by machine; mechanical: an automatic reply to a familiar question. 3. a. Capable of firing continuously until ammunition is exhausted or the trigger is released: an automatic rifle. b. Semiautomatic: an automatic pistol. n. Idiom: 1. An automatic machine or device. 2. a. An automatic firearm. b. A semiautomatic firearm. 3. A transmission or a motor vehicle with an automatic gear-shifting mechanism. on automatic Functioning by or as if by automatic machine or device. [From Greek automatos : auto-, auto- + -matos, willing; see men-1 in the Appendix of Indo-European roots.] au′to·mati·cal·ly adv. au′to·ma·tici·ty (-mə-tĭsĭ-tē) n. |
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