A preposterous person is -

Preposterous (adjective)Meaning: Contrary to reason or common sense; utterly absurd or ridiculous Bengali meaning: অসংগত ; অসম্ভব ; ভ্রান্ত ; নির্বুদ্ধিতাপূর্ণSynonym: absurd, ridiculous, foolish, stupid, ludicrous, farcical, laughable, comical, risible, hare-brained, asinine, inane, nonsensical, pointless, senseless, insane, unreasonable, irrational, illogicalAntonym: reasonable, sensibleMeaning of other wordAbsurd এর অর্থ উদ্ভট বা অসঙ্গগতSource: Oxford Dictionary