trig·ger | \ˈtri-gər \

Definition of trigger 

(Entry 1 of 2)

1a : a piece (such as a lever) connected with a catch or detent as a means of releasing it especially : the part of the action moved by the finger to fire a gun

b : a similar movable part by which a mechanism is actuated trigger of a spray gun

2 : something that acts like a mechanical trigger in initiating a process or reaction


triggered; triggering\ˈtri-g(ə-)riŋ \

Definition of trigger (Entry 2 of 2)

transitive verb

1a : to release or activate by means of a trigger especially : to fire by pulling a mechanical trigger trigger a rifle

b : to cause the explosion of trigger a missile with a proximity fuse

2 : to initiate, actuate, or set off by a trigger an indiscreet remark that triggered a fight a stimulus that triggered a reflex

3 : to cause an intense and usually negative emotional reaction in (someone) Water had a way of triggering my brother and making ordinary, everyday weather take a frightening turn for the worse.— Ingrid Law

intransitive verb

: to release a mechanical trigger

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Other Words from trigger


triggered \ˈtri-gərd \ adjective

Synonyms & Antonyms for trigger

Synonyms: Verb

activate, actuate, crank (up), drive, move, run, set off, spark, start, touch off, turn on

Antonyms: Verb

cut, cut out, deactivate, kill, shut off, turn off

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Examples of trigger in a Sentence


Smoke triggered the fire alarm. The timer was set to trigger the bomb in exactly one hour. His remarks triggered a public outcry. Certain foods trigger his headaches. The power outage was triggered by heavy rains.
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Recent Examples on the Web: Noun

The trigger for such a shift would be Merkel’s ouster. Alan Crawford,, "As Merkel’s Power Drains, the Threat to Europe Grows," 27 June 2018 Every button tap and block-completion triggers sound effects synced to the tune. Sam Machkovech, Ars Technica, "Lumines Remastered turns the Nintendo Switch into a full-body vibration party," 26 June 2018 Manziel can't help but wonder, however, about the looming struggle to eschew the triggers, the stimuli of his downfall. Lorenzo Reyes, USA TODAY, "For Johnny Manziel, recovery takes priority amid comeback in CFL," 6 June 2018 Genetic mutations in cells are cancer's trigger, causing those cells to grow out of control. Jonathan Lapook, CBS News, "Groundbreaking treatment saves life of woman with late-stage breast cancer," 4 June 2018 When an officer pulls the trigger, two wires with probes on the ends are released and become embedded in the person’s body. Gina Barton, Milwaukee Journal Sentinel, "Police Tasers: How do they work? What are the risks?," 23 May 2018 After oversleeping and missing his bus to school, a Michigan teen was almost killed by a trigger-happy homeowner while trying to ask for directions. Paula Rogo,, "White Homeowner Almost Kills Black Teen Who Knocked On His Door To Ask For Directions," 14 Apr. 2018 The trigger-happy wing has the ability to finish at the rim and also a reliable jump shot, especially at the mid-range level. Special To The Oregonian,, "Michigan commit Ignas Brazdeikis will look to score at Nike Hoop Summit," 10 Apr. 2018 Unbeknownst to him, the package had been intercepted days earlier by authorities and was equipped with a tracking device and trigger, the special agent's affidavit states. Zak Koeske, Daily Southtown, "2 south suburban men indicted in conspiracy to import, sell fentanyl analogues from China: officials," 9 Mar. 2018

Recent Examples on the Web: Verb

The simultaneous observations could yield clues to how those eruptions are triggered. Dennis Normile, Science | AAAS, "New China space missions will watch for colliding black holes, solar blasts," 11 July 2018 The thinking is that, because stress taxes your immune system, that increases your risk for developing psoriasis and may worsen or trigger existing psoriasis. Emily Wang, SELF, "‘Queer Eye’ Star Jonathan Van Ness Reveals He’s Been ‘Psoriasis Flare Free’ for Six Months," 29 June 2018 ACT Geary Theater, 415 Geary St. 415-749-2228,—M. Crowder Not reviewed Antigone The third play in Sophocles’ Oedipus trilogy in which Antigone’s love of her family triggers the ultimate destruction of the city of Thebes., "Theater capsule reviews and listings, week of July 1," 28 June 2018 The innovation forever changed the Tex-Mex restaurant business (placing bars front and center) and triggered the craze for Tex-Mex food. Franz Lidz, Smithsonian, "The Uniquely Texan Origins of the Frozen Margarita," 27 June 2018 In the past, such a move has been a last-ditch option, often triggered by war. Timothy Puko, WSJ, "U.S. and Allies Consider Possible Oil-Reserve Release," 13 July 2018 The center said a total of 3,430 people had evacuated their homes in nine cities and counties by Wednesday morning to avoid landslides triggered by heavy rainfall. Washington Post, "Typhoon Maria barrels into China after pounding Taiwan," 12 July 2018 The center said a total of 3,430 people had evacuated their homes in nine cities and counties by Wednesday morning to avoid landslides triggered by heavy rainfall. Fox News, "Typhoon Maria barrels into China after pounding Taiwan," 11 July 2018 Temperatures reached the low to mid-90s Tuesday in most of Massachusetts, but scattered showers and thunderstorms triggered by an approaching cold front are expected to bring needed relief. Jeremy C. Fox,, "Cooling rain is expected in some places in Mass. tonight," 10 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'trigger.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of trigger


1621, in the meaning defined at sense 1a


1916, in the meaning defined at transitive sense 1a

History and Etymology for trigger


alteration of earlier tricker, from Dutch trekker, from Middle Dutch trecker one that pulls, from trecken to pull — more at trek

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Phrases Related to trigger

quick on the trigger

Statistics for trigger

Last Updated

30 Sep 2018

Look-up Popularity

Time Traveler for trigger

The first known use of trigger was in 1621

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More Definitions for trigger



English Language Learners Definition of trigger

 (Entry 1 of 2)

: a lever on a gun that you pull to fire the gun

: something that causes something else to happen



English Language Learners Definition of trigger (Entry 2 of 2)

: to cause (something, such as an alarm) to start functioning

: to cause (a bomb) to explode

: to cause (something) to start or happen


trig·ger | \ˈtri-gər \

Kids Definition of trigger

: the part of the lock of a gun that is pressed to release the hammer so that it will fire

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Comments on trigger

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


a state of commotion or excitement

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