Meaning of portentous

por•ten•tous

Pronunciation: (pôr-ten'tus, pōr-), [key]
— adj.
  1. of the nature of a portent; momentous.
  2. ominously significant or indicative: a portentous defeat.
  3. marvelous; amazing; prodigious.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.
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