The quality of being one of a kind:
— That singularity distinguished him from all his companions.

synonym: uniqueness.

Roget 79: speciality, specialite^†; individuality, individuity^†; particularity, peculiarity; idiocrasy etc. (tendency) 176; personality, characteristic, mannerism, idiosyncrasy; specificness etc. adj.^†; singularity etc. (unconformity) 83; reading, version, lection; state; trait; distinctive feature; technicality; differentia.    particulars, details, items, counts; minutiae.    I, self, I myself; myself, himself, herself, itself.    ... show more

Roget 83: nonconformity etc. 82; unconformity, disconformity; unconventionality, informality, abnormity^†, abnormality, anomaly; anomalousness etc. adj.^†; exception, peculiarity; infraction of law, breach, of law, violation of law, violation of custom, violation of usage, infringement of law, infringement of custom, infringement of usage; teratism^†, eccentricity, bizarrerie^†, oddity, je ne sais quoi [Fr.], monster, monstrosity, rarity; freak, freak of Nature, weirdo, mutant; rouser, snorter [U.S.].    individuality, idiosyncrasy, originality, mannerism.    aberration; irregularity; variety; singularity; exemption; salvo etc. (qualification) 469.    nonconformist; nondescript, character, original, nonesuch, nonsuch^†, monster, prodigy, wonder, miracle, curiosity, flying fish, black sheep, black swan, lusus naturae [Lat.], rara avis [Lat.], queer fish; mongrel, random breed; half-caste, half-blood, half-breed; metis [Lat.], crossbreed, hybrid, mule, hinny, mulatto; tertium quid [Lat.], hermaphrodite.    [Mythical animals] phoenix, chimera, hydra, sphinx, minotaur; griffin, griffon; centaur; saggittary^†; kraken, cockatrice, wyvern, roc, dragon, sea serpent; mermaid, merman, merfolk^†; unicorn; Cyclops, men whose heads do grow beneath their men whose heads do grow beneath their shoulders" [Othello]; teratology.    [unconformable to the surroundings] fish out of water; neither one thing nor another, neither fish nor fowl, neither fish flesh nor fowl nor good red neither fish flesh nor fowl nor good red herring; one in a million, one in a way, one in a thousand; outcast, outlaw; off the beaten track; oasis.    ... show more

Polish: jednokrotność, pojedynczość

Strangeness by virtue of being remarkable or unusual.

Dutch: bijzonderheid