tacker vs staple gun

tacker and staple gun both are nouns.

Word	Noun	Adjective	Verb	Adverb
tacker	Yes	No	No	No
staple gun	Yes	No	No	No

As nouns, tacker and staple gun are synonyms defined as:

Other synonyms of tacker include staplegun.

tacker (noun)	staple gun (noun)
a hand-held machine for driving staples home	a hand-held machine for driving staples home
a sewer who fastens a garment with long loose stitches
a worker who fastens things by tacking them (as with tacks or by spotwelding)