• WordNet 3.6
    • n unguis any rigid body structure composed primarily of keratin
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Webster's Revised Unabridged Dictionary
    • Unguis (Zoöl) One of the terminal hooks on the foot of an insect.
    • Unguis The nail, claw, talon, or hoof of a finger, toe, or other appendage.
    • Unguis (Bot) The slender base of a petal in some flowers; a claw; called also ungula.
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Century Dictionary and Cyclopedia
    • n unguis The horny, nail-like covering of the tip of the bill found in ducks and geese.
    • n unguis A nail, claw, or hoof of any animal.
    • n unguis A measure of length, about half an inch. In anatomy: The human lacrymal bone: so called because it resembles the human finger-nail: more fully called os unguis.
    • n unguis The hippocampus minor, or calcar, of the brain. Also unguis avis, unguis Halleri.
    • n unguis In entomology, one of the curved claws at the extremity of an insect's tarsus. Generally there are two of these on each tarsus, but they may be united; sometimes there is a projection or claw-like organ, the onychium or empodium, between the true claws. The ungues are attached to a very small piece, which, according to Huxley, is a true joint, though the preceding joint is generally called the last of the tarsus: this piece may be expanded beneath into a cushion-like organ, the pulvillus. Some entomologists apply the term unguis to the last tarsal joint, including the two claws, which are then distinguished as unguiculi. The ungues assume various forms, which are of great importance in classification. The two claws may be more or less united or connate, even nearly to the tips. When forming only a slight angle with each other they are said to be divergent, and when spreading widely they are divaricate. They are cleft when each claw is split from the tip so that there is an upper and a lower division; unequally cleft when these divisions are of unequal size; cleft with movable parts when the divisions are movable on each other; bifid when the divisions are side by side instead of one over the other. According to the processes on the lower or concave surface, ungues are toothed when each has one pointed process; serrate when there are several small pointed teeth; serrulate when these processes are fine and bristle-like; pectinate when they are long, slender, and numerous; appendiculate when each claw has a membranous appendicle beneath. The claws may be unequal in size; and when they can be turned back on the last tarsal joint they are said to be subchelate.
    • n unguis In botany, the claw or lower contracted part of some petals, by which they are attached to the receptacle, as in the pink, the mustard, Cleome, etc. It is analogous to the petiole of a leaf. Also ungula. See cut under claw.
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Chambers's Twentieth Century Dictionary
    • ns Unguis a nail, claw, hoof, or any structure resembling such: the narrow part of the base of a petal, acting as a footstalk: a measure equal to the length of the nail of the little finger, ½-inch
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Webster's Revised Unabridged Dictionary
L., nail, claw, or hoof
Chambers's Twentieth Century Dictionary
L. unguis, a nail.


In literature:

The malar bone, and the os unguis or lachrymal, are more or less developed according to the species considered.
"Artistic Anatomy of Animals" by Édouard Cuyer