Meniscus

n.	1.	A crescent.
	2.	(Opt.) A lens convex on one side and concave on the other.
	3.	(Anat.) An interarticular synovial cartilage or membrane; esp., one of the intervertebral synovial disks in some parts of the vertebral column of birds. Converging meniscus See Lens.

Noun

1.

meniscus - a disk of cartilage that serves as a cushion between the ends of bones that meet at a point

achromatic lens, astigmatic lens, burning glass, camera, coated lens, concave lens, concavo-convex lens, condenser, convex lens, crescent, crescent moon, eyeglass, eyepiece, glass, half-moon, hand lens, horseshoe, lens, lunula, lunule, magnifier, magnifying glass, object glass, objective, objective prism, ocular, prism, reader, reading glass, scythe, semicircle, sickle, telephoto lens, toric lens, varifocal lens, zoom lens