Unguis

Part of speech: noun

Pronunciation: /ˈʌŋ.ɡwɪs/

Definitions

1. A hard, protective covering made of keratin found on the tips of fingers and toes in humans and some animals ; a claw, talon, or similar curved structure used for grasping or defense ; a small, hornlike plate forming a part of certain invertebrates' anatomy
2. A tough, curved structure composed of keratin present at the end of digits for protection and tool use ; a sharp, hooked appendage in various animals aiding in hunting or climbing ; a chitinous or keratinous element in invertebrate exoskeletons serving as a point or tip
3. A rigid, nail-like organ covering the dorsal side of digits made of keratin enabling protection and manipulation ; a claw or talon serving as offense or defense mechanism in vertebrates ; a terminal, plate-like feature of some invertebrates that functions as a gripping or stabbing device

Etymology: Latin "unguis" meant "nail, claw, hoof," and it is the same word that gave English "onyx." The connection is a doublet: the two English words came into the language by different routes from the same Latin root. "Onyx" was borrowed from Greek "onyx," which also meant "claw" or "fingernail," and it was used for a banded stone whose layers looked like the colored rings of a nail or a claw. "Unguis" entered English as a technical term for the hard covering over the tip of a digit, and it has stayed almost entirely within anatomy and zoology. Because the word was taken straight from Latin rather than passing through everyday speech, it kept its learned, clinical feel. Its meaning has barely moved in more than two thousand years: a fingernail, a toenail, or the claw of an animal. The gemstone and the body part share a single ancestor, but only the stone word became common in ordinary English.

Synonyms: claw, nail, talon, hoof, hoof