onych-, onycho-, ony-, -onychia, -onychial, -onychium, -onyx- +

(Greek: claw, nail; fingernails, toenails)

macronychia, megalonychia
1. The abnormal length, or thickness, of the fingernails or toenails.
2. A condition of having unusually large nails.
megalonychosis
Hypertrophy (abnormal enlargement) of the fingernails and toenails.
melanonychia
1. Black pigmentation (coloring) of the nails.
2. Blackening of the nails by melanin pigmentation.
onycha
1. The precious stone called onyx (a semi-pellucid gem with variously colored zones or veins, a variety of chalcedony or a subspecies of quartz, a mineral also called, "white agate".
2. Etymology: from Old French oniche, from Latin onyx, onychis; from Greek onyx, "onyx-stone"; originally "claw, fingernail".

So called because the mineral's color sometimes resembles that of a fingernail, pink with white streaks.

onychalgia (s) (noun) (no pl)
Pain in the nails or claws: The elderly Mr. Lawson's fingernails were becoming cracked and were hurting him, and after being examined by his dermatologist, he was informed that he had a case of onychalgia.
onychalgia nervosa
1. Extreme sensitivity of the fingernails and/or toenails.
2. Extreme sensitivity of apparently normal fingernails and toenails.
onychatrophia, onychatrophy
1. Atrophy (shrinking in size) of the fingernails and toenails.
2. Failure of a proper development of the fingernails and toenails.
onychauxis
1. The overgrowth of the nails.
2. Hypertrophy of a nail without deformity.
onychectomy
The surgical excision (removal) of a fingernail or toenail.
onychexallaxis
Degeneration, or deterioration, or a change from a higher to a lower form of the fingernails and toenails.
onychia
1. Inflammation of the nailbed with possible suppuration (generating purulent matter or forming pus) and loss of the nail.
2. An infection of a finger or toe, attended with ulceration at the base of the nail, and terminating in the destruction of the nail.
onychia maligna
A form of onychia occurring in debilitated people; characterized by an ulcer in the matrix of the nail, which becomes discolored and is thrown off.
onychia superficialis undulata
A rare type of fingernail and toenail disease seen in secondary syphilis, characterized by superficial waves and ripples across the nails.
onychitis
Inflammation of the nail bed, resulting in loss of the nail.
onychoclasis
Breaking of the fingernails or toenails.

A cross reference, directly or indirectly, involving a word unit meaning "nail (finger, toe); claw": ungu-.