英语词源字典 - 在线词源网站

deep (adj.)[deep 词源字典]: Old English deop "profound, awful, mysterious; serious, solemn; deepness, depth," deope (adv.), from Proto-Germanic *deupaz (cognates: Old Saxon diop, Old Frisian diap, Dutch diep, Old High German tiof, German tief, Old Norse djupr, Danish dyb, Swedish djup, Gothic diups "deep"), from PIE *dheub- "deep, hollow" (cognates: Lithuanian dubus "deep, hollow, Old Church Slavonic duno "bottom, foundation," Welsh dwfn "deep," Old Irish domun "world," via sense development from "bottom" to "foundation" to "earth" to "world").

Figurative senses were in Old English; extended 16c. to color, sound. Deep pocket "wealth" is from 1951. To go off the deep end "lose control of oneself" is slang first recorded 1921, probably in reference to the deep end of a swimming pool, where a person on the surface can no longer touch bottom. When 3-D films seemed destined to be the next wave and the biggest thing to hit cinema since talkies, they were known as deepies (1953).[deep etymology, deep origin, 英语词源]
natatorium (n.): 1890, New Englandish word for "swimming pool," from Latin natator "swimmer" (from nare "to swim") + -ium, neuter suffix. Latin nare is from PIE root *sna- "to swim" (cognates: Sanskrit snati "bathes;" Avestan snayeite "washes, cleans;" Armenian nay "wet, liquid," Greek notios "wet, damp," nekhein "to swim;" Middle Irish snaim "I swim," snam "a swimming"). Middle English had natatorie "a pool, bath," early 14c., from Latin.
pool (n.1): "small body of water," Old English pol "small body of water; deep, still place in a river," from West Germanic *pol- (cognates: Old Frisian and Middle Low German pol, Dutch poel, Old High German pfuol, German Pfuhl). As a short form of swimming pool it is recorded from 1901. Pool party is from 1965.
swimming (n.): late 14c., "act of propelling the body through water," verbal noun from swim (v.). Swimming hole is from 1855, American English; swimming pool is from 1881.