WordWeb Online

1. Not usual, common or ordinary
   "a scene of unusual beauty"; "a man of unusual ability"; "cruel and unusual punishment"; "an unusual meteorite"
    
2. Being definitely out of the ordinary and unexpected; slightly odd or even a bit weird
   - strange
    
3. Not commonly encountered
   "two-career families are no longer unusual"

See also: antic [archaic], crazy, curious, different, eerie, eery, exotic, extraordinary, fantastic, fantastical, freaky, funny, gothic, grotesque, odd, oddish, other, out-of-the-way, peculiar, quaint, queer, rum [Brit], rummy, singular, spooky, unaccustomed, uncommon, unique, usualness, weird

Antonym: usual

Encyclopedia: Unusual