Meaning

• A finger-operated lever used to fire a gun.

  "Just pull the trigger."

• A similar device used to activate any mechanism.

• An event that initiates others, or incites a response.

  "Sleeping in an unfamiliar room can be a trigger for sleepwalking."

• A concept or image that upsets somebody.

  "I can't watch that violent film. Blood is one of my triggers."

• An event, experience or other stimulus that initiates a traumatic memory or action in a person.

• An electronic transducer allowing a drum, cymbal, etc. to control an electronic drum unit or similar device.

• 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.

• A pulse in an electronic circuit that initiates some component.

• An SQL procedure that may be initiated when a record is inserted, updated or deleted; typically used to maintain referential integrity.

• A text string that, when received by a player, will cause the player to execute a certain command.

• A catch to hold the wheel of a carriage on a declivity.

Meaning

• To fire a weapon.

• To initiate something.

  "The controversial article triggered a deluge of angry letters from readers."

• To spark a response, especially a negative emotional response, in (someone).

  "This story contains a rape scene and may be triggering for rape victims."

• To activate; to become active.