Coop
Middle English cowpe ; related to Dutch kuip ‘vat’ and German Kufe ‘cask’, based on Latin cupa . Compare with cooper.
wiktionary
From Middle English cǒupe, cupe, from Old English cȳpe(“ basket, cask”) or possibly from Middle Dutch cûpe (compare modern Dutch kuip, Saterland Frisian kupe, Middle Low German kûpe), from Old Saxon *kûpa, côpa(“cask”) (compare Middle Low German kôpe, Old High German chôfa, chuofa, Middle High German kuofe, modern German Kufe(“cask (feminine)”), probably from Latin cūpa, Medieval Latin cōpa(“cask”) (thus a doublet of coupe, cup, and keeve). However, the Oxford English Dictionary notes that if the word is from Latin, “it is difficult to account for the umlaut in Old English cýpe”.
Possibly from coop, above. Sense 2 may be from English coup(“to tilt, overturn, upset”).
Origin uncertain; compare English cop(“ top, summit (especially of a hill); head”).
From cooperative, by shortening.
etymonline
coop (n.)
"small cage for poultry," mid-14c., coupe, from Old English cype, cypa "large wicker basket, cask," akin to Middle Dutch kupe, Swedish kupa, and all probably from Latin cupa "tub, cask," from PIE *keup- "hollow mound" (see cup (n.)).
coop (v.)
"put into a coop, confine in a narrow compass" (usually with up), 1560s, from coop (n.). Related: Cooped; cooping.
