horsefly vs cleg

horsefly and cleg both are nouns.

Word	Noun	Adjective	Verb	Adverb
horsefly	Yes	No	No	No
cleg	Yes	No	No	No

As nouns, horsefly and cleg are synonyms defined as:

horsefly and cleg: large swift fly the female of which sucks blood of various animals

Other synonyms of horsefly include clegg, horse fly.

horsefly (noun)	cleg (noun)
large swift fly the female of which sucks blood of various animals	large swift fly the female of which sucks blood of various animals
winged fly parasitic on horses