The definition of a trigger is the mechanism on a gun that makes it shoot a bullet or anything that starts a series of events.
(noun)Trigger is defined as to fire a gun or to start a series of events or emotions.
(verb)See trigger in Webster's New World College Dictionary
noun
Origin: earlier tricker < Du trekker < trekken, to draw, pull: see trek
transitive verb
See trigger in American Heritage Dictionary 4
noun
Origin:
Origin: Dutch trekker
Origin: , from Middle Dutch trecker
Origin: , from trecken, to pull
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