The Oxford Thesaurus An A-Z Dictionary of Synonyms - uniqueadj.

1) single, lone, (one and) only, solitary, one of a kind, sui generis: Natural forces conspired to create this unique situation. 2) unequalled, unparalleled, unrivalled, incomparable, inimitable, peerless, unmatched, unsurpassed, unexcelled, second to none: Stimble's genius is unique in the annals of proctology.