unique

I

(New American Roget's College Thesaurus)

adj. sole, single; singular, only, sui generis; unequaled, matchless, unparalleled, unprecedented, unusual, rare. See unconformity, exclusion, inequality, unity.

II

(Roget's IV) modif.

1. [Existing only in one known example]

Syn. single, sole, peerless, matchless, incomparable, unprecedented, unparalleled, unequaled, unrivaled, unsurpassed, novel, nonpareil, unapproachable, unapproached, anomalous, individual, sole, sui generis (Latin), unexampled, lone, different, unequaled.

Ant. common*, frequent, many*.

2. [Rare]

Syn. uncommon, freakish, bizarre; see unusual 2 .

III

(Roget's 3 Superthesaurus) a.

one-of-a-kind, single, sole, unparalleled, lone, only, incomparable, distinctive, unprecedented, extraordinary, special, peculiar, strange, in a class by itself.

ANT.: common, commonplace, run-of-the-mill, *common as a brick

IV

(Roget's Thesaurus II) adjective 1. Alone in a given category: lone, one, only, particular, separate, single, singular, sole, solitary. Idioms: first and last, one and only. See INCLUDE. 2. Without equal or rival: alone, incomparable, matchless, nonpareil, only, peerless, singular, unequaled, unexampled, unmatched, unparalleled, unrivaled. See SAME.