n.[C]

1. （槍砲的）扳機；觸發器
   He pulled the trigger and the bottle was shot to pieces.

   他扣動扳機，瓶子當即被打得粉碎。

2. 起動裝置；扳柄；閘柄
3. 能引起反應的刺激物[（+for）]
   Some people say that violent movies are potential triggers for juvenile delinquency.

   一些人說暴力影片可能引起青少年犯罪。

vt.

1. 扣扳機開（槍）；發射
2. 觸發，引起[（+off）]
   His action has triggered off a crisis.

   他的行動已經引起一場危機。

   A spark triggered the explosion.

   一粒火星引起了這場爆炸。

vi.

1. 鬆開扳柄（或閘柄等）

n.

1. a device that releases a spring or catch and so sets off a mechanism, especially in order to fire a gun.
2. an event that causes something to happen.

v.

1. cause (a device) to function.
2. (also trigger something off) cause to happen or exist.