n. pl. id·i·o·syn·cra·sies 1. A structural or behavioral characteristic peculiar to an individual or group. 2. A physiological or temperamental peculiarity. 3. An unusual individual reaction to food or a drug. [Greek idiosunkrāsiā : idio-, idio- + sunkrāsis, mixture, temperament (sun-, syn- + krāsis, a mixing; see kerə- in the Appendix of Indo-European roots).] id′i·o·syn·cratic (-sĭn-krătĭk) adj. id′i·o·syn·crati·cal·ly adv. |
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