[W]e pull'd aſide the Tricker, and obſerv'd, that according to our expectation the force of the Spring of the Lock vvas not ſenſibly abated by the abſence of the Air.1659 December 30 (date written), Robert Boyle, “[Experiment 14]”, in New Experiments Physico-Mechanicall, Touching the Spring of the Air, and Its Effects […], Oxford, Oxfordshire: […] H[enry] Hall, printer to the University, for Tho[mas] Robinson, published 1660, →OCLC, page 89:
2
A similar device used to activate any mechanism.
3
An event that initiates others, or incites a response.
Sleeping in an unfamiliar room can be a trigger for sleepwalking.
4
Something that triggers an ASMR response.
5
A concept or image that upsets somebody by sparking a negative emotional response.
emotional trigger
I can't watch that violent film. Blood is one of my triggers.
6
Human sciences, Psychology, Sciences An event, experience or other stimulus that initiates a traumatic memory or a strong reaction in a person.
7
Entertainment, Lifestyle, Music An electronic transducer allowing a drum, cymbal, etc. to control an electronic drum unit or similar device.
8
Entertainment, Lifestyle, Music A device that manually lengthens (or sometimes shortens) the slide or tubing of a brass instrument, allowing the pitch range to be altered while playing.
Computing, Databases, Engineering, Mathematics, Natural sciences, Physical sciences, Sciences An SQL procedure that may be initiated when a record is inserted, updated or deleted; typically used to maintain referential integrity.
11
Archaic A catch to hold the wheel of a carriage on a declivity.
12
Grammar, Human sciences, Linguistics, Sciences An argument whose semantic role determines the choice of a verbal affix, in certain Austronesian languages.
Etymology Originally tricker, from Dutch trekker (“pull”, noun, as in drawer-pull, bell-pull), from Dutch trekken (“to drag, draw, pull”).
1
To fire (a weapon).
A U235 bomb would therefore need to incorporate a gun weighing ten tons. Then there was the question of initiating or triggering the bomb.2011, Jim Baggott, The First War of Physics, Pegasus Books, →ISBN:
2
To cause, to precipitate, to bring (something) about in response or as a result.
The controversial article triggered a deluge of angry letters from readers.
The accident followed torrential early morning rain that triggered widespread flooding across Scotland's tracks, including south of Carmont.2020 August 26, Philip Haigh, “Network News: Three die in ScotRail landslip derailment at Carmont”, in Rail, page 6:
1 more example
A 35-year-old woman’s flutter was triggered by increasing the depth of breathing and by (electrical) stimulation of the diaphragm.2017, Michael Chiou, BA; María Victoria Herrero; John R. Bach, MD; Jeffrey L. Cole, MD; and Enrique Luis Gonzales, AAS, CRT, RRT, “Treatment of Idiopathic Diaphragm Flutter”, in CHEST^(https://journal.chestnet.org/article/S0012-3692(17)30175-7/pdf):
3
Figuratively To spark a response, especially a negative emotional response, in (a person).
This story contains a rape scene and may be triggering for rape victims.
People get triggered simply by seeing a Trump.2019, Donald Trump Jr., Triggered, Center Street, →ISBN:
1 more example
I encountered a forum user who didn't agree with me, so I wrote some comments with my political slogans to trigger that clueless kiddo.2020 January 25, Ernesto Londoño, Letícia Casado, “Glenn Greenwald in Bolsonaro’s Brazil”, in The New York Times, →ISSN, archived from the original on 25 Jan 2020:
Sodium nitrite (750 ppm) was added after the alarm triggered at three hours, and corrosion did not occur for over eight hours.1997, Mill Operators' Conference, page 182: