unforgettable

from WordNet (r) 3.0 (2006)

unforgettable
    adj 1: impossible to forget [ant: {forgettable}]

from The Collaborative International Dictionary of English v.0.48

Unforgettable \Un`for*get"ta*ble\, a.
   Not forgettable; enduring in memory.
   [1913 Webster]

         Pungent and unforgettable truths.        --Emerson.
   [1913 Webster]

from Moby Thesaurus II by Grady Ward, 1.0

32 Moby Thesaurus words for "unforgettable":
      celebrated, conspicuous, distinguished, eminent, esteemed,
      estimable, exceptional, extraordinary, haunting, indelible, marked,
      memorable, nagging, noble, notable, noteworthy, obsessive, of mark,
      outstanding, persistent, prestigious, prominent, rare, recurrent,
      remarkable, rememberable, reputable, salient, signal, special,
      striking, telling

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