gallfly vs gall gnat

gallfly and gall gnat both are nouns.

Word	Noun	Adjective	Verb	Adverb
gallfly	Yes	No	No	No
gall gnat	Yes	No	No	No

As nouns, gallfly and gall gnat are synonyms defined as:

gallfly and gall gnat: fragile mosquito-like flies that produce galls on plants

Other synonyms of gallfly include gall midge.

gallfly (noun)	gall gnat (noun)
any of various insects that deposit their eggs in plants causing galls in which the larvae feed	fragile mosquito-like flies that produce galls on plants
small solitary wasp that produces galls on oaks and other plants
fragile mosquito-like flies that produce galls on plants