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Affixes

onycho-

The nails.

Greek onux, onukh‑, nail or claw.

Onychomycosis (Greek mukēs, fungus) is a fungal infection of the nails; onycholysis (Greek lusis, loosening) is the separation or loosening of a nail from its bed; onychogryphosis (Gk grupōsis, hooking of the nails) is the thickening and curving sideways of a nail, usually of the big toe; onychophagia (Greek phagein, to eat) is the formal term for biting one's nails.