What does "preposterous" mean?

Preposterous: Contrary to nature or reason; not adapted to the end; utterly and glaringly foolish; unreasonably absurd; perverted. "Most preposterous conclusions." Shak. Preposterous ass, that never read so far! Shak. See Absurd. -- Pre*pos"ter*ous*ly, adv. -Pre*pos"ter*ous*ness, n.

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