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adjective au·to·mat·ic \ˌȯ-tə-ˈma-tik\

Simple Definition of automatic

  • of a machine or device : having controls that allow something to work or happen without being directly controlled by a person

  • of a gun : shooting many bullets very quickly when the trigger is pulled

  • : happening or done without deliberate thought or effort

Source: Merriam-Webster's Learner's Dictionary

Full Definition of automatic

  1. 1 a :  largely or wholly involuntary; especially :  reflex 5 <automatic blinking of the eyelids> b :  acting or done spontaneously or unconsciously c :  done or produced as if by machine :  mechanical <the answers were automatic>

  2. 2 :  having a self-acting or self-regulating mechanism <an automatic transmission>

  3. 3 of a firearm :  firing repeatedly until the trigger is released

automaticallyplay \-ti-k(ə-)lē\ adverb
automaticityplay \-mə-ˈti-sə-tē, -ma-\ noun

Examples of automatic in a sentence

  1. Without thinking, he gave an automatic reply.

  2. She always has an automatic smile for everyone.

Origin of automatic

Greek automatos self-acting, from aut- + -matos (akin to Latin ment-, mens mind) — more at mind

First Known Use: 1748

Synonym Discussion of automatic

spontaneous, impulsive, instinctive, automatic, mechanical mean acting or activated without deliberation. spontaneous implies lack of prompting and connotes naturalness <a spontaneous burst of applause>. impulsive implies acting under stress of emotion or spirit of the moment <impulsive acts of violence>. instinctive stresses action involving neither judgment nor will <blinking is an instinctive reaction>. automatic implies action engaging neither the mind nor the emotions and connotes a predictable response <his denial was automatic>. mechanical stresses the lifeless, often perfunctory character of the response <a mechanical teaching method>.

Other Weapons and Explosives Terms



noun au·to·mat·ic

Simple Definition of automatic

  • : a gun that shoots many bullets very quickly : an automatic weapon

  • : a vehicle that changes gears by itself at different speeds : a car with automatic transmission

Source: Merriam-Webster's Learner's Dictionary

Full Definition of automatic

  1. 1 :  a machine or apparatus that operates automatically: as a :  an automatic firearm b :  an automatic transmission

  2. 2 :  a semiautomatic firearm

  3. 3 :  audible

Examples of automatic in a sentence

  1. Will your next car be a manual or an automatic?


First Known Use of automatic


AUTOMATIC Defined for Kids


adjective au·to·mat·ic \ˌȯ-tə-ˈma-tik\

Definition of automatic for Students

  1. 1 :  involuntary <automatic blinking of eyelids>

  2. 2 :  being a machine or device that allows something to work without being directly controlled by a person <an automatic washer>

automatically \-ti-kə-lē\ adverb

Law Dictionary


adjective au·to·mat·ic

Legal Definition of automatic

  1. :  happening or existing through the operation of a preexisting arrangement that is triggered by some event; specifically :  happening or existing through the operation of law <automatic reversal> <an automatic appeal>

automatically adverb

Seen and Heard

What made you want to look up automatic? Please tell us where you read or heard it (including the quote, if possible).


a division or portion of a pool or whole

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