trigger

American  

[trig-er] / ˈtrɪg ər /

noun

1. a small projecting tongue in a firearm that, when pressed by the finger, actuates the mechanism that discharges the weapon.

2. a device, as a lever, the pulling or pressing of which releases a catch or spring.

3. anything, as an act or event, that serves as a stimulus and initiates or precipitates a reaction or series of reactions.

4. something that evokes the memory of a traumatic experience, setting off an intense negative emotional reaction.

   This issue of the magazine contains accounts of sexual assault, and may be a trigger for some people.

5. Slang. triggerman.

---

verb (used with object)

1. to initiate or precipitate (a chain of events, scientific reaction, psychological process, etc.).

   Their small protest triggered a mass demonstration.

2. to fire or explode (a gun, missile, etc.) by pulling a trigger or releasing a triggering device.

   He accidentally triggered his rifle.

3. to set off a negative emotional reaction in (someone), as by evoking the memory of a traumatic experience, repeatedly raising a sensitive issue, etc..

   I missed seeing my mom in the ICU before she died, and imagining her there triggers me every time I see ICU footage on TV.

verb (used without object)

1. to release a trigger.

2. to become active; activate.

idioms

1. quick on the trigger, quick to act or respond; impetuous; alert.

trigger British  

/ ˈtrɪɡə /

noun

1. a small projecting lever that activates the firing mechanism of a firearm

2. machinery a device that releases a spring-loaded mechanism or a similar arrangement

3. any event that sets a course of action in motion

---

verb

1. (usually foll by off) to give rise (to); set off

2. to fire or set in motion by or as by pulling a trigger

trigger More Idioms  

More idioms and phrases containing trigger

• quick on the draw (trigger)

---

Other Word Forms

• triggered adjective
• triggerless adjective

Etymology

Origin of trigger

First recorded in 1615–25; earlier tricker, from Dutch trekker, equivalent to trekk(en) “to pull” + -er -er ¹

Example Sentences

Public uproar over the Novi Sad disaster triggered the resignation of the prime minister and the collapse of the government earlier this year.

From Barron's

Maddie's first TikTok video about baby loss - which she posted with a trigger warning - shows her and her husband in the Blossom Suite, gently swaying with Teddy while tears stream down their faces.

From BBC

The World Bank expects agricultural commodity prices to remain stable to slightly lower in 2026, though weather shocks and crop diseases could still trigger volatility.

From Barron's

"The constant bouncing of the pickleball is not only annoying but also subtly triggers stress, disrupts sleep, and increases the risk of cardiovascular disease," according to state-run VTC News website.

From Barron's

With further research, doctors hope to establish whether AI can actually trigger mental-health problems.

From The Wall Street Journal

Related Words

• bring about
• cause
• generate
• produce
• prompt
• provoke
• set off
• spark
• start