The meaning of TRIGGER is 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.

A trigger is something that sets off a flashback, transporting the person back to the traumatic event.

to initiate or precipitate (a chain of events, scientific reaction, psychological process, etc.). Their small protest triggered a mass demonstration. to fire or explode (a gun, missile, etc.) by pulling …

If something acts as a trigger for another thing such as an illness, event, or situation, the first thing causes the second thing to begin to happen or exist.

To set off; initiate: remarks that triggered bitter debates; allergens that trigger asthma attacks. 2. To fire or explode (a weapon or an explosive charge). [Dutch trekker, from Middle Dutch …

Definition of trigger noun in Oxford Advanced American Dictionary. Meaning, pronunciation, picture, example sentences, grammar, usage notes, synonyms and more.

He pulled/squeezed the trigger. Police officers are trained to not be too quick on the trigger. [=eager to fire a gun]

anything that causes a reaction: a trigger for the fight. to cause or begin (a chain of events): Inflation triggered unemployment. to fire or explode (a gun, etc.) by pulling a trigger. …

trigger, n.¹ meanings, etymology, pronunciation and more in the Oxford English Dictionary

to cause, begin, or set off (an action or series of actions). The earthquake triggered the tsunami. Getting fired from his job triggered his rage. Do you know exactly what triggers your allergy …