An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

1) An apparently hollow formation in the structure of an astronomical object, for example a sizable hole on the surface of a → molecular cloud created by → ultraviolet photons of a → massive star.
2) In a semiconductor laser, two reflective parallel edges forming a resonator that amplifies the light through stimulated emission.

From M.Fr. cavité, from L.L. cavitas "hollowness," from L. cavus "hollow."

Kâvâk, related to verb kâvidan (kâftan) "to dig; to examine, investigate," cf. L. cavus "hollow" (E. derivatives: cavity, concave, cave, excavate), Gk. koilos "hollow," Armenian sor, PIE *kowos "hollow."

The interior of the → nose. It is the structure which extends from the external opening, the → nostrils, to the → pharynx, where it joins the respiratory system.

→ nasal; → cavity.