名詞 hair-trigger:

1. a gun trigger that responds with little pressure
   同義詞：hair trigger

hair-trig.ger

adj.（形容詞）
Responding to the slightest provocation or stimulation:
一觸即發(fā)的：對(duì)最細(xì)微的刺激或挑動(dòng)起反應(yīng)的：
例句：
a hair-trigger temper; a hair-trigger reaction.
一觸即怒的脾氣；一觸即發(fā)的反應(yīng)