Words related to *keue-
late 15c., "that which is heaped up, an accumulated mass," from Latin accumulationem (nominative accumulatio) "a heaping up," noun of action from past-participle stem of accumulare "to heap up, amass," from ad "to," here perhaps emphatic (see ad-), + cumulare "heap up," from cumulus "heap" (from suffixed form of PIE root *keue- "to swell"). Meaning "act of heaping up" is from c. 1600.
"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.
Old English cirice, circe "place of assemblage set aside for Christian worship; the body of Christian believers, Christians collectively; ecclesiastical authority or power," from Proto-Germanic *kirika (source also of Old Saxon kirika, Old Norse kirkja, Old Frisian zerke, Middle Dutch kerke, Dutch kerk, Old High German kirihha, German Kirche).
This is probably [see extensive note in OED] borrowed via an unrecorded Gothic word from Greek kyriake (oikia), kyriakon doma "the Lord's (house)," from kyrios "ruler, lord," from PIE root *keue- "to swell" ("swollen," hence "strong, powerful").
Greek kyriakon (adj.) "of the Lord" was used of houses of Christian worship since c. 300, especially in the East, though it was less common in this sense than ekklesia or basilike. An example of the direct Greek-to-Germanic transmission of many Christian words, via the Goths; probably it was used by West Germanic people in their pre-Christian period.
The word also was picked up by the Slavic tongues, probably via Germanic (Old Church Slavonic criky, Russian cerkov). Finnish kirkko, Estonian kirrik are from Scandinavian. Romance and Celtic languages use variants of Latin ecclesia (such as French église, 11c.).
Phonetic spelling from c. 1200, established by 16c. For vowel evolution, see bury. After the Reformation, church was used for any particular Christian denomination agreeing on doctrine and forms of worship.
As an adjective, "pertaining to a church," from 1570s. Church-bell was in late Old English. Church-goer is from 1680s. Church-key "key of a church door" is from early 14c.; slang use for "can or bottle opener" is by 1954, probably originally U.S. college student slang. Church-mouse (1731) "a mouse supposed to live in a church" (where there is nothing for it to eat) is proverbial in many languages for poverty.
"white crystalline alkaloid present in opium," 1838, codeina, from French codéine, coined, with chemical suffix -ine (2), from Greek kodeia "poppy head," related to koos "prison," literally "hollow place;" kodon "bell, mouth of a trumpet;" koilos "hollow, hollowed out, spacious, deep," all from PIE root *keue- "to swell," also "vault, hole." Modern form is from 1881.
order of lobe-finned fishes, 1850, from Modern Latin Coelacanthus (genus name, 1839, Agassiz), from Greek koilos "hollow" (from PIE root *keue- "to swell," also "vault, hole") + akantha "spine" (from PIE root *ak- "be sharp, rise (out) to a point, pierce"). So called from the hollow fin rays supporting the tail in fossil remains.
Thought to have gone extinct 66 million years ago until a living one was fished up off the east coast of South Africa Dec. 22, 1938. The specimen was noticed by museum curator Marjorie Courtney-Latimer, who wrote a description of it to South African ichthyologist J.L.B. Smith.
I stared and stared, at first in puzzlement. I did not know any fish of our own, or indeed of any seas like that; it looked more like a lizard. And then a bomb seemed to burst in my brain, and beyond that sketch and the paper of the letter, I was looking at a series of fishy creatures that flashed up as on a screen, fishes no longer here, fishes that had lived in dim past ages gone, and of which only fragmentary remains in rock are known. [J.L.B. Smith, "Old Fourlegs: The Story of the Coelacanth," 1956]