Chowder was probably invented in Newfoundland by early French-and-English-speaking colonists, and because of this French influence, it is thought that the word developed from French chaudiere, which described a kind of large pot. This is from the Latin word caldaria, also "cooking pot", which is from the earlier Latin word caldarium, which meant "hot bath" and makes sense if you understand cooking as the process of giving your ingredients a very hot bath. This is from an even earlier Latin word, which was alternatively spelled caldus and calidus and meant "hot". As we go further back, linguists reconstruct caldus as being from the Proto-Italic term kaleo, which stems from Proto-Indo-European kelh, still meaning "hot". Once chaudiere was adopted to denote the soup, awesome New England accents altered it so the ch became hard and the ending took on its current form.
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