to trigger the water works
A trigger is a metal lever that when pulled discharges a gun.
You shoot the gun by pulling the trigger.
To trigger can also mean the start of a process––violent protests might trigger a revolution.
Certain scents, places, or old love songs can be said to trigger, or activate, memories. If you get weepy when you hear the national anthem, that may be because it triggers thoughts of family, home, baseball and the Fourth of July. For someone in frail health, a seemingly minor problem like getting a common cold, might trigger a series of physical responses that end up landing them in the hospital.
Definitions of trigger
noun 1. lever that activates the firing mechanism of a gun 2. device that activates, releases, causes something to happen
noun an act that sets in motion some course of events
synonyms:induction, initiation
verb put in motion or move to act
“trigger a reaction”
synonyms: activate, actuate, set off, spark, spark off, touch off, trigger off, trip