triggerman vs hitman

triggerman and hitman both are nouns.

Word	Noun	Adjective	Verb	Adverb
triggerman	Yes	No	No	No
hitman	Yes	No	No	No

As nouns, triggerman and hitman are synonyms defined as:

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

triggerman (noun)	hitman (noun)
a professional killer who uses a gun	a professional killer who uses a gun