[1] : The Collaborative International Dictionary of English v.0.48

idiosyncrasy \id`iosyn"crasy\, n.; pl. idiosyncrasies. gr.
   ?; 'i`dios proper, peculiar + ? a mixing together, fr. ? to
   mix together; ? with + ? to mix: cf. f. idiosyncrasie. see
   idiom, and crasis.
   a peculiarity of physical or mental constitution or
   temperament; a characteristic belonging to, and
   distinguishing, an individual; characteristic susceptibility;
   idiocrasy; eccentricity.
   1913 webster

         the individual mind . . . takes its tone from the
         idiosyncrasies of the body.              --i. taylor.
   idiosyncratic
see also:
idiosyncrasies idiom crasis 

[2] : WordNet (r) 2.0

idiosyncrasy
     n : a behavioral attribute that is distinctive and peculiar to
         an individual syn: foible, mannerism
see also:
foible mannerism 

[3] : Moby Thesaurus II by Grady Ward, 1.0

142 moby thesaurus words for "idiosyncrasy":
   aberration, abnormality, animus, anomaly, aptitude, aroma,
   attribute, badge, banner, bent, bias, brand, cachet, cast,
   character, characteristic, conceit, configuration, constitution,
   crackpotism, crank, crankiness, crankism, crotchet, crotchetiness,
   cut, deviancy, deviation, device, diathesis, differentia,
   differential, differentness, disposition, distinctive feature,
   divergence, dottiness, earmark, eccentricity, erraticism,
   erraticness, feature, figure, flavor, freakiness, freakishness,
   grain, gust, habit, hallmark, idiocrasy, image, impress,
   impression, inclination, index, indicant, indicator, individualism,
   insignia, irregularity, keynote, kidney, kink, leaning, lineaments,
   maggot, make, makeup, mannerism, mark, marking, measure,
   mental set, mettle, minauderie, mind, mind-set, mold, nature,
   nonconformity, note, oddity, odor, particularity, peculiar trait,
   peculiarity, picture, predilection, predisposition, preference,
   proclivity, propensity, property, quality, queerness, quip, quirk,
   quirkiness, representation, representative, savor, seal, set,
   shape, sigil, sign, signal, signature, singularity, slant, smack,
   specialty, stamp, strain, strangeness, streak, stripe, sure sign,
   symptom, taint, tang, taste, telltale sign, temper, temperament,
   tendency, token, trademark, trait, trick, trick of behavior, turn,
   turn of mind, twist, type, unconventionality, unnaturalness, warp,
   whim, whimsicality, whimsy

Idiosyncrasy >> I Words
Idiosyncrasy, definition of term: Idiosyncrasy
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