Trigger, as an alarm, is a device that sets off an alarm when it is tripped. It is usually used to alert people of danger or to deter intruders. Trigger alarms are commonly found in homes, businesses, and other places where security is important. They can be set off by motion, sound, or other triggers. The two crossword solutions for the term trigger, as an alarm, are SETOFF (6 letters) and TRIP (4 letters). SETOFF is a verb meaning to cause something to start or begin suddenly, while TRIP is a verb meaning to activate or set off an alarm.