peradventure

nouns

doubt or uncertainty as to whether something is the case
"this proves beyond peradventure that he is innocent"
peradventure
is a type of (narrower)
the state of being unsure of something
doubt, doubtfulness, dubiety, dubiousness, incertitude, uncertainty

adverbs

by chance
"perhaps she will call tomorrow"; "we may possibly run into them at the concert"; "it may peradventure be thought that there never was such a time"
maybe, mayhap, peradventure, perchance, perhaps, possibly