What is "idio-"

Idio- \Id"i*o-\ ([i^]d"[i^]*[-o]-). A combining form from the Greek 'i`dios, meaning private, personal, peculiar, distinct.

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

pre. Forming compound words having the sense of individuality, peculiarity, separateness.