Cavity

google

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mid 16th century: from French cavité or late Latin cavitas, from Latin cavus ‘hollow’.

wiktionary

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Mid 16th century borrowing from Middle French cavité or Late Latin cavitās, from cavus(“hollow, excavated, concave”) +‎ -tās(“-ity”, nominal suffix).

etymonline

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cavity (n.)

"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").