squirter vs squirt gun

squirter and squirt gun both are nouns.

Word	Noun	Adjective	Verb	Adverb
squirter	Yes	No	No	No
squirt gun	Yes	No	No	No

As nouns, squirter and squirt gun are synonyms defined as:

squirter and squirt gun: plaything consisting of a toy pistol that squirts water

Other synonyms of squirter include water gun, water pistol.

squirter (noun)	squirt gun (noun)
plaything consisting of a toy pistol that squirts water	plaything consisting of a toy pistol that squirts water