early 15c., cripte, "grotto, cavern," from Latin crypta "vault, cavern," from Greek krypte "a vault, crypt" (short for krypte kamara "hidden vault"), fem. of kryptos "hidden," verbal adjective from kryptein "to hide," which is of uncertain origin. Comparison has been made to Old Church Slavonic kryjo, kryti "to hide," Lithuanian kráuti "to pile up." Beekes writes that krypto "is formally and semantically reminiscent of [kalypto]; the verbs may have influenced each other." For this, see calypto-. But he adds, "However, since there is no good IE etymology, the word could be Pre-Greek." Meaning "underground burial vault or chapel in a church" is attested by 1789.

"perigee of the moon, perihelion of a planet" (plural apsides), 1650s, from Latin apsis "arch, vault" (see apse).

"large, natural cave under the earth," late 14c., from Old French caverne (12c.) "cave, vault, cellar," from Late Latin caverna "cave," from Latin cavus "hollow" (from PIE root *keue- "to swell," also "vault, hole"). In Old English such a land feature might be called an eorðscræf.

"a hollow place in the earth, a natural cavity of considerable size and extending more or less horizontally," early 13c., from Old French cave "a cave, vault, cellar" (12c.), from Latin cavea "hollow" (place), noun use of neuter plural of adjective cavus "hollow," from PIE root *keue- "to swell," also "vault, hole." Replaced Old English eorðscrafu.

in architecture, "an S-shaped molding," 1670s, said to be from a corruption of French ogive "diagonal rib of a vault" of a type normal in 13c. French architecture, earlier augive, a word of unknown origin. According to Watkins, in part from Latin via "way, road" (see via). Related: ogival. Middle English had ogif (late 13c.) "a stone for the diagonal rib of a vault," from the French word and Medieval Latin ogiva.

before vowels coel-, word-forming element in scientific compounds meaning "hollow," from Latinized form of Greek koilos "hollow," from PIE root *keue- "to swell," also "vault, hole."

"a hollow place, empty space in the body," 1540s, from French cavité (13c.), from Late Latin cavitatem (nominative cavitas) "hollowness," from Latin cavus "hollow" (from PIE root *keue- "to swell," also "vault, hole").

c. 1400, "a concave surface," from Old French concavit "hollow, concavity" (14c.) or directly from Latin concavitatem (nominative concavitas), from Latin concavus "hollow, arched, vaulted, curved," from con-, here perhaps an intensive prefix (see con-), + cavus "hollow" (from PIE root *keue- "to swell," also "vault, hole"). From 1570s as "state of being concave."