Definitions
1.nounSomething that is possibly true.
2.nounAn answer that shows neither agreement nor disagreement."The results of the poll were inconclusive. We got two yeses, three nos, and four maybes."
3.nounA future event that may or may not happen."About your raise: it's a big maybe."
4.adjectivePossible; uncertain.
5.adverbModifies a verb, indicating a lack of certainty: it may be that...
6.adverb(as a pro-sentence) Perhaps that is true (expressing no commitment to a decision or a neutral viewpoint to a statement).