cockchafer vs May bug

cockchafer and May bug both are nouns.

Word	Noun	Adjective	Verb	Adverb
cockchafer	Yes	No	No	No
May bug	Yes	No	No	No

As nouns, cockchafer and May bug are synonyms defined as:

cockchafer and May bug: any of various large European beetles destructive to vegetation as both larvae and adult

Other synonyms of cockchafer include May beetle, Melolontha melolontha.

cockchafer (noun)	May bug (noun)
any of various large European beetles destructive to vegetation as both larvae and adult	any of various large European beetles destructive to vegetation as both larvae and adult
	any of various large usually brown North American leaf-eating beetles common in late spring; the larvae feed on roots of grasses etc.