hit man vs triggerman

hit man and triggerman both are nouns.

Word	Noun	Adjective	Verb	Adverb
hit man	Yes	No	No	No
triggerman	Yes	No	No	No

As nouns, hit man and triggerman are synonyms defined as:

Other synonyms of hit man include gun, gun for hire, gunman, gunslinger, hired gun, hitman, shooter, torpedo.

hit man (noun)	triggerman (noun)
a professional killer who uses a gun	a professional killer who uses a gun