Question

trigger 【trigger】n.扳机 v.引起；促使When you squeeze the trigger, a round or rounds of ammunition are fired.当你紧按扳机，一发或几发子弹就射出了。When the burglar tripped the wire it triggered an alarm.当窃贼绊到铁丝网，引起警铃大作。

Accepted Answer

['trɪɡər] 
triggerlever that activates the firing mechanism of a gun
A trigger is a metal lever that when pulled discharges a gun. You shoot the gun by pulling the trigger. 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.
All forms of 'trigger' will appear on average once every 594 pages.trigger

Front	trigger
Pron	['trɪɡər]
Back	【trigger】 n.扳机 v.引起；促使 When you squeeze the trigger, a round or rounds of ammunition are fired. 当你紧按扳机，一发或几发子弹就射出了。 When the burglar tripped the wire it triggered an alarm. 当窃贼绊到铁丝网，引起警铃大作。
Vocab	triggerlever that activates the firing mechanism of a gun A trigger is a metal lever that when pulled discharges a gun. You shoot the gun by pulling the trigger. 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. All forms of 'trigger' will appear on average once every 594 pages. trigger

Trigger Lever Gun Trɪɡər N.扳机 V.引起；促使 Squeeze Round