lunate

/loo-neyt/US // ˈlu neɪt //UK // (ˈluːneɪt) //

月牙形,月牙儿,月牙形的,月球

Definitions

adj.形容词 adjective

n.名词 noun

1
- : Anatomy. the second bone from the thumb side of the proximal row of bones of the carpus.
- : a crescent-shaped, microlithic artifact mounted in a haft to form a composite tool, mostly Mesolithic in origin.

Frustule elliptical; valve lunate, with straight ventral margin.
Valve lunate, with acute ends; ventral margin straight; ventral side very narrow.
Cl., to which as a variety Cleve unites Lewis' form, appears to resemble it only in the lunate marks.
The chief distinction lies in the lunate tail, which has a keel on either side at base, as in the mackerels.
It is of a narrow lunate form, highly convex, the disk destitute of sculpture, and the eyes prominent.