The definition of a hair trigger is a gun trigger that goes off with a very light squeeze.(noun)
An example of a hair trigger is a pistol that's been adjusted so it goes off very easily.
Hair trigger defines something that responds or happens easily or without cause.(adjective)
An example of hair trigger is a person who gets angry instantly; a hair trigger temper.
See hair trigger in Webster's New World College Dictionary
Origin: see hair trigger
See hair trigger in American Heritage Dictionary 4
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