blow fly vs greenbottle

blow fly and greenbottle both are nouns.

Word	Noun	Adjective	Verb	Adverb
blow fly	Yes	No	No	No
greenbottle	Yes	No	No	No

As nouns, greenbottle is a hyponym of blow fly; that is, greenbottle is a word with a more specific, narrower meaning than blow fly:

blow fly: large usually hairy metallic blue or green fly; lays eggs in carrion or dung or wounds
greenbottle: blowfly with brilliant coppery green body

Other hyponyms of blow fly include bluebottle, Calliphora vicina, greenbottle fly.

blow fly (noun)	greenbottle (noun)
large usually hairy metallic blue or green fly; lays eggs in carrion or dung or wounds	blowfly with brilliant coppery green body