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definitions

idio-

  1. a combining form meaning “proper to one,” “peculiar,” used in the formation of compound words: idiomorphic.

Origin of idio-

< Greek, combining form of ídios (one's) own, personal, private, separate, distinct
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for idio-

idio-

combining form
  1. indicating peculiarity, isolation, or that which pertains to an individual person or thingidiolect

Word Origin for idio-

from Greek idios private, separate
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for idio-

word-forming element meaning "one's own, personal, distinct," from Greek idio-, comb. form of idios "own, personal, private, one's own" (see idiom).

Online Etymology Dictionary, © 2010 Douglas Harper
idio- in Medicine

idio-

pref.
  1. One's own; private; personal:idiosyncrasy.
  2. Distinct; separate:idioventricular.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.