catastrophic
The definition for catastrophic is "Relating to extreme misfortune." Used in a sentence: The effects of the massive hurricane were catastrophic.
civility
The definition for civility is "Politeness." Used in a sentence: The usually unruly Thomas acted with great civility when his favorite uncle visited.
inauspicious
The definition for inauspicious is "Not favorable." Used in a sentence: Gary believed the black foreboding sky was an inauspicious sign.
iridescent
The definition for iridescent is "Having a lustrous or attractivve quality." Used in a sentence: The movie star's iridescent presence charmed even the hardened reporter.
preclude
The definition for preclude is "To rule out in advance." Used in a sentence: "Having cake now will preclude dessert later," said Amber's mother.