tears

tears watery secretion of the lacrimal gland, which is located at the outer corner of the eye socket immediately above the eyeball. Tearing, or lacrimation, is a continuous and largely involuntary process stimulated by the autonomic nervous system. Fluid is secreted into the lacrimal lake, the area between the eyeball and the upper eyelid, and spread across the surface of the eye by blinking. Tears serve to bathe and lubricate the cornea, the sensitive outer covering of the eyeball. Typically, the fluid either evaporates or is drained off through tiny canals at the inner corner of the eye, but in times of excessive tearing the apparatus is overwhelmed and tears overflow the eyes.

Bibliography: See T. Lutz, Crying: The Natural and Cultural History of Tears (1999).

tears (teerz) pl. n. the fluid secreted by the lacrimal glands to keep the front of the eyeballs moist and clean. Tears contain lysozyme, an enzyme that destroys bacteria.

tears Salty fluid secreted by glands that moistens the surface of the eye. It cleanses and disinfects the surface of the eye and also brings nutrients to the cornea.