section_path: Etymology
section_name: Etymology
paragraph_text: Etymology
  
  The word cheese comes from Latin caseus, from which the modern word casein is derived. The earliest source is from the proto-Indo-European root *kwat-, which means "to ferment, become sour". That gave rise to cīese or cēse (in Old English) and chese (in Middle English). Similar words are shared by other West Germanic languages — West Frisian tsiis, Dutch kaas, German Käse, Old High German chāsi —all from the reconstructed West-Germanic form *kāsī, which in turn is an early borrowing from Latin.
  
  The Online Etymological Dictionary states that "cheese" derives from:
  
  Old English cyse (West Saxon), cese (Anglian)... from West Germanic *kasjus (source also of Old Saxon kasi, Old High German chasi, German Käse, Middle Dutch case, Dutch kaas), from Latin caseus "cheese" (source of Italian cacio, Spanish queso, Irish caise, Welsh caws).
  
  The Online Etymological Dictionary states that the word is of:
  
  unknown origin; perhaps from a PIE root *kwat- "to ferment, become sour" (source also of Prakrit chasi "buttermilk;" Old Church Slavonic kvasu "leaven; fermented drink," kyselu "sour," - kyseti "to turn sour;" Czech kysati "to turn sour, rot;" Sanskrit kvathati "boils, seethes;" Gothic hwaþjan "foam").
  
  When the Romans began to make hard cheeses for their legionaries ' supplies, a new word started to be used: formaticum, from caseus formatus, or "cheese shaped in a mold". It is from this word that the French fromage, standard Italian formaggio, Catalan formatge, Breton fourmaj, and Occitan fromatge (or formatge) are derived. Of the Romance languages, Spanish, Portuguese, Romanian, Tuscan and some Southern Italian dialects use words derived from caseus (queso, queijo, caș, cacio and caso for example). The word cheese is occasionally employed, as in Head cheese, to mean "shaped in a mold".