Unknown according to De Vaan.[1] The old hypothesis deriving it fromProto-Indo-European*kwath₂(“to ferment, become sour”)[2] has the problem that*w isn't supposed to disappear in Latin (the expected outcome would start withqua- and notca-). In this case, the cognates listed under*kweth₂- are perhaps loans from the samesubstrate source as the Latin term.
‘‘Let me squeeze full udders, may mycheese repay me with money, and may the wicker strainer give a passage to the liquid whey.’’ (A shepherd’s prayer toPales.)
^De Vaan, Michiel (2008) “cāseus”, inEtymological Dictionary of Latin and the other Italic Languages (Leiden Indo-European Etymological Dictionary Series; 7), Leiden, Boston: Brill,→ISBN,pages96-7
“caseus”, inCharlton T. Lewis and Charles Short (1879)A Latin Dictionary, Oxford: Clarendon Press
“caseus”, inCharlton T. Lewis (1891)An Elementary Latin Dictionary, New York: Harper & Brothers
"caseus", in Charles du Fresne du Cange’sGlossarium Mediæ et Infimæ Latinitatis (augmented edition with additions by D. P. Carpenterius, Adelungius and others, edited by Léopold Favre, 1883–1887)
caseus inGaffiot, Félix (1934)Dictionnaire illustré latin-français, Hachette.
“caseus”, inHarry Thurston Peck, editor (1898),Harper's Dictionary of Classical Antiquities, New York: Harper & Brothers
