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

(Greek: claw, nail; fingernails, toenails)

onychocrauria
Brittleness of the fingernails or toenails.
onychocryptosis
An ingrown (nonvisible) nail [a toenail, one edge of which is overgrown by the nailfold, producing a pyogenic granuloma (nodule or overgrowth of tissue); as a result of faulty trimming of the toenails or pressure from a tight shoe].
onychodystrophy
1. Dystrophic changes (disorders arising from defective or faulty nutrition) in the nails occurring as a congenital (birth) defect or due to any illness or injury that may cause a malformed nail.
2. Any distortion of a nail; a symptom seen in several diseases.
onychogenic
A reference to the formation of the fingernails or toenails.
onychogram
A recording of the nail pulse and capillary circulation.
onychograph
An instrument for recording the capillary blood pressure as shown by the circulation under the nail.
onychography
1. The observation and recording of the fingernail and toenail pulses and capillary circulations.
2. The procedure of recording the blood pressure in the capillaries beneath the nails.
onychogryposis, onychogryphosis
1. A thickening and curvature of the nails which is associated with an increase in length such that the nails resemble a ram's horn.
2. Abnormally thick curved fingernails or toenails, giving them a clawlike appearance.
onychoheterotopia
1. Abnormally located nails.
2. Abnormal placement of nails on the fingers or toes.
onychoid
Resembling a nail of the finger or the toe in structure or form.
onychology
The medical study of the nails and their disorders.
onycholysis
1. The separation of all or part of a fingernail or thumbnail from its bed, associated with psoriasis or a fungal skin condition.
2. Loosening of the nail from the nail bed, usually starting at the border of the nail.

The nail tends to turn whitish or yellowish, reflecting the presence of air under it.

onychoma
A tumor of a toenail, a fingernail, or a nailbed.
onychomadesis
A spontaneous, or rapid, shedding of fingernails and toenails, starting at the base and extending forward.
onychomalacia
Abnormal softness of the finger and/or toe nails.

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