mayhap vs peradventure

mayhap is not a noun while peradventure is a noun.

Word	Noun	Adjective	Verb	Adverb
mayhap	No	No	No	Yes
peradventure	Yes	No	No	Yes

As adverbs, mayhap and peradventure are synonyms defined as:

Other synonyms of mayhap include maybe, perchance, perhaps, possibly.

mayhap (noun)	peradventure (noun)
	doubt or uncertainty as to whether something is the case

mayhap (adverb)	peradventure (adverb)
by chance	by chance