1. (a.) Being without a like or equal; unmatched; unequaled; unparalleled\; single in kind or excellence; sole.

2. (n.) A thing without a like; something unequaled or unparalleled.

a certain absolute almost unheard-of alone an another any any one appropriate atomic authentic avant-garde azygous beguiling bewildering beyond compare beyond comparison breakaway celibate characteristic creative different distinctive distinguished easily first either else enigmatic exceptional exclusive extraordinary fabulous facile princeps fantastic fascinating first and last firsthand fresh idiocratic idiosyncratic imaginative immortal impair in character incomparable incomprehensible inconceivable incredible individual indivisible infrequent inimitable integral intrinsic invincible irreducible lone marked marvelous matchless miraculous monadic monistic new not that sort not the same not the type novel nulli secundus odd of a sort of another sort of sorts offbeat one one and only only only-begotten original other other than otherwise outlandish particular passing strange peculiar peerless phenomenal prodigious proper puzzling quintessential rare recherche remarkable revolutionary scarce second to none seldom met with seldom seen sensational separate simple single singular slow sole solid solitary solo sparse special strange striking stupendous sui generis true to form unanalyzable unapproachable unapproached unbeatable uncommon uncustomary underived undivided undreamed-of unequaled unexampled unexcelled unexpected unfamiliar unfrequent unheard-of uniform unimaginable unitary unmatchable unmatched unordinary unpaired unparagoned unparalleled unpeered unprecedented unrepeatable unrepeated unrivaled unsurpassable unsurpassed unthinkable unthought-of unusual unwonted whole without equal without parallel wonderful wondrous