from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A white band of cholesterol that forms at the edge of the cornea
- n. A low, horizontal cloud typically forming at the leading edge of thunderstorm outflow
- n. An elastic band around the base of the arolium, a pad at the end of the leg of certain insects
- n. An arc-shaped band of thickened sexine extending between two apertures on a pollen grain or spore
from The Century Dictionary and Cyclopedia
- n. In anatomy, an arch, bow, or ring.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a whitish deposit in the shape of an arc that is sometimes seen in the cornea
Borrowed from Latin arcus. (Wiktionary)