ETYM Greek; idios proper, peculiar + syn with + kerannynai a mixing together: cf. French idiosyncrasie. Related to Idiom, and Crasis.
An behavioral attribute that is distinctive and peculiar to an individual; SYN. foible, mannerism.
Mental or physical peculiarity; eccentricity; special sensitivity to a drug.

1. A strange attitude or habit; SYN. queerness, quirk, quirkiness, crotchet.
2. Eccentricity that is not easily explained; SYN. oddness.

1. A distinguishing trait; SYN. specialness, specialty, speciality, distinctiveness.
2. An odd or unusual characteristic; SYN. distinctive feature.
3. Oddity, quirk

ETYM Written also querk.
A narrow groove beside a beading.