hair-trig·​ger | \ ˈher-ˌtri-gər How to pronounce hair-trigger (audio) \

Definition of hair-trigger

 (Entry 1 of 2)

1 : immediately responsive to the slightest stimulus a hair-trigger temper
2 : delicately adjusted or easily disrupted

hair trigger


Definition of hair trigger (Entry 2 of 2)

: a gun trigger so adjusted as to permit the firearm to be fired by a very slight pressure

Examples of hair-trigger in a Sentence

Recent Examples on the Web: Noun Many experts have urged Biden to reform the launch system, perhaps requiring two or more people to authorize nuclear weapons use, or taking the whole system off a hair trigger altogether. Kyle Mizokami, Popular Mechanics, "Here's How Trump Will Pass the Nuclear Football to Biden," 20 Jan. 2021 The speed and number of people involved in the destruction showed Minneapolis remains on a hair trigger nearly three months after the police killing of George Floyd, an unarmed Black man, on Memorial Day. Nicole Norfleet, Star Tribune, "IDS Center closed to public, downtown businesses began to clean up," 27 Aug. 2020 So far there’s been no launch, but the strange shooting death this weekend of a South Korean official who might have been looking to enter the North by boat nonetheless highlights the hair trigger on which the Peninsula still rests. John Bolton, WSJ, "China Needs to Answer for Its North Korea Policy," 29 Sep. 2020 Those who did not lose their homes live on a hair trigger, choked for weeks by thick smoke and always girded for a quick escape. Thomas Fuller, New York Times, "Wildfires Are Latest Risk in the Rewarding Quiet of Gold Country," 18 Sep. 2020 The quick escalation and number of people involved in the destruction showed Minneapolis remains on a hair trigger three months after the police killing of George Floyd, an unarmed Black man. John Ewoldt, Star Tribune, "Businesses assess damage after riots and looting hit Nicollet Mall in downtown Minneapolis," 27 Aug. 2020 The controller is notable for mechanical buttons that respond on a hair trigger. Popular Science, "Upgrade your Xbox One game with these amazing controllers," 9 June 2020 The demon core, destined for use in a weapon of mass destruction, was designed to have a hair trigger. Julian G. West, The Atlantic, "The Atomic-Bomb Core That Escaped World War II," 2 Apr. 2018 The accelerator's hair trigger delivered more responsiveness for quicker pep off the line, and the ride felt much firmer — even choppy at times. Jennifer Geiger, USA TODAY, "Review: Audi's SQ5 blazes new SUV trails," 23 Feb. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'hair-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 hair-trigger


1834, in the meaning defined at sense 1


1802, in the meaning defined above

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Time Traveler for hair-trigger

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The first known use of hair-trigger was in 1802

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Cite this Entry

“Hair-trigger.” Dictionary, Merriam-Webster, Accessed 7 Mar. 2021.

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More Definitions for hair-trigger



English Language Learners Definition of hair-trigger

 (Entry 1 of 2)

: becoming angry very easily

hair trigger


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

: a trigger on a gun that needs very little pressure to cause the gun to shoot

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