disapproval If you describe something as preposterous, you mean that it is extremely unreasonable and foolish. The whole idea was preposterous. = ludicrous + preposterously pre·pos·ter·ous·ly Some prices are preposterously high. completely unreasonable or silly = absurd (praeposterus , from prae- ( PRE-) + posterus ( POSTERIOR))
completely devoid of wisdom or good sense; "the absurd excuse that the dog ate his homework"; "that's a cockeyed idea"; "ask a nonsensical question and get a nonsensical answer"; "a contribution so small as to be laughable"; "it is ludicrous to call a cottage a mansion"; "a preposterous attempt to turn back the pages of history"; "her conceited assumption of universal interest in her rather dull children was ridiculous"
Contrary to nature or reason; not adapted to the end; utterly and glaringly foolish; unreasonably absurd; perverted