squirt gun vs water pistol

squirt gun and water pistol both are nouns.

Word	Noun	Adjective	Verb	Adverb
squirt gun	Yes	No	No	No
water pistol	Yes	No	No	No

As nouns, squirt gun and water pistol are synonyms defined as:

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

Other synonyms of squirt gun include squirter, water gun.

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