ungu- +

(Latin: nail, claw, hoof)

ad unguem (Latin)
Perfectly.

Literally, "to a fingernail": Ad unguem is used to convey the thought of accomplishing something well or precisely.

In ancient times, a sculptor would test the smoothness of a finished surface by running a fingernail over it.

dystrophia unguium
Dystrophy (disorder arising from defective or faulty nutrition) of the fingernails and the toenails.
ex ungue leonem
From a claw, the lion.

You may tell the lion by its claws or from a sample we can judge the whole.

exungulate
To pare off, or to trim; such as, fingernails, toenails, a hoof, etc.
exungulation
The paring, or trimming, of the fingernails, toenails, hoofs, etc.
grysosis unguium
A thickening and curvature of the fingernails and toenails that are associated with an increase in length such that the nail resembles a ram's horn.
matrix unguis
The area of the corium (dermis) on which the nail rests.

It is extremely sensitive and presents numerous longitudinal ridges on its surface.

According to some anatomists, the nail bed is the portion covered by the body of the nail, the nail matrix being only the part on which the root of the nail rests.

multungulate
Having a hoof with more than two parts.
polynychia, polyunguia, polyonychia
The presence of supernumerary nails or beyond the normal number of nails on fingers or toes.
solidungula
A tribe of ungulates (animals with hoofs) which includes the horse, ass, and related species, constituting the family Equidae.
solidungular
Having single hoofs instead of divided hoofs.
solidungulate
Having a single, undivided hoof on each foot; such as, a horse.
solidungulous
Having single hoofs instead of having divided hoofs.
subungual
Under the nail or hoof.
Terretur minimo pennae stridore columba unguibus, accipiter, saucia facta tuis.
O hawk, the dove that's been wounded by your talons is frightened by the least flutter of a feather.

A Latin idiom. The French, Italians, and Spanish have an equivalent idiom: "A scalded cat is afraid of cold water." Another similar idiom: "A burned child is afraid of a puff of smoke."

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