Origins
Chowder is a thick, stew-like soup of the New England coast, most famously made with clams, potatoes, onions, salt pork, and either cream (New England clam chowder) or tomatoes (Manhattan clam chowder). The name is not a description of the dish but of the pot it was cooked in: a chowder is, strictly speaking, anything boiled in a chaudière, the large iron kettle of the French fishermen who plied the Grand Banks. English chowder is first attested in North American sources in the 1730s, borrowed from Canadian French chaudière, which descends from Late Latin caldāria "warming-pot," from Latin calidus "warm, hot," and behind that from the Proto-Indo-European root *kelh₁- "warm." Chowder thus belongs to the Indo-European family through its Latin ancestry, and its semantic story is the very common one of a vessel-name passing to the food cooked in the vessel.
The earliest documented use of the word in English comes from the Boston Evening Post in 1732, in a piece of doggerel verse that treats chowder as already familiar fare among sailors. Benjamin Franklin's Poor Richard's Almanack (1745) includes a recipe-poem for chowder, and by the late eighteenth century the dish was so fixed a part of New England diet that communal chowder parties, called chowders, were organised social events along the Massachusetts and Rhode Island coast. Herman Melville devotes a chapter of Moby-Dick (1851) to "Chowder," Ishmael and Queequeg eating clam and cod chowder at the Try Pots Inn in Nantucket: "Chowder for breakfast, and chowder for dinner, and chowder for supper, till you began to look for fish-bones coming through your clothes." Oliver Wendell Holmes and John Greenleaf Whittier also wrote about chowder as a token of maritime New England life. The OED traces the transatlantic flow in detail: the word crossed the Atlantic with Breton and Norman fishermen, landed in Newfoundland and the Gaspé, and spread southward into New England with the cod and whale trades.
The ultimate source, French chaudière, is not merely "cooking pot" but specifically a large cauldron, often hung on a tripod over an open fire or suspended in a hearth. In medieval French chaudière appears in the chansons de geste as the pot in which meat is boiled for large companies of soldiers or guests; in modern French the word still names both domestic boilers and industrial heating vessels (a chaudière à vapeur is a steam boiler). The form comes through Old French chaudiere from Late Latin caldāria, feminine of caldārius "pertaining to warming," derived from calēre "to be warm" and calidus "warm." From the same Latin root English has inherited or re-borrowed a large family of words: cauldron (through Anglo-Norman caudron), caldera (the volcanic basin, through Spanish), nonchalant (not warming up, not excited), chafe (to warm by friction, through Old French chaufer), chafing dish, scald (through Old French escalder), calorie, calorific, and calenture (a tropical fever).
French Influence
Cognates of chaudière in the Romance languages show the same vessel-sense throughout: Italian caldaia, Spanish caldera (the pot, and by extension the volcanic crater), Portuguese caldeira (also the geological crater), Catalan caldera, Romanian căldare. All descend from the same Late Latin caldāria, and in several of them the word has taken on secondary technical meanings (boiler, still, vat, volcanic caldera) while retaining the basic sense of a pot for heating. In contrast, chowder itself has few direct cognates in modern European languages — it is a specifically Anglo-American culinary term, and most other languages either borrow the English word for the dish (French chowder américain, German Chowder) or have no equivalent. The word also survives in regional British dialect as chowter or jowter, used in Devon and Cornwall for a fish-seller, which may share the same Norman-French root, though this connection is sometimes disputed.
In modern English chowder has broadened semantically but remained rooted in its maritime origins. New England clam chowder is creamy and white; Manhattan clam chowder is tomato-based and red — a culinary divide so bitter that in 1939 Maine state legislator Seth Bradstreet actually introduced House Bill 251 to make it illegal to put tomatoes in chowder. Rhode Island chowder is a clear-broth middle path, and Delaware, New Jersey, and the Outer Banks all claim local variants. Corn chowder, fish chowder, and seafood chowder preserve the older sense of any thick, potato-based stew of boiled ingredients, while shrimp chowder, salmon chowder, and even vegan mushroom chowder have joined the catalogue in recent decades. The more metaphorical chowder-headed (meaning muddle-headed, confused, a thick soup for brains) is recorded from the early nineteenth century, possibly a folk-etymological reshaping of an older British jolter-headed or jolt-headed; the related form chowder-pate appears in nineteenth-century American humour writing. The OED still marks the base sense of the noun as "a stew of fish or clams boiled with salt pork, onions, and biscuit," a definition whose ingredients trace directly back to the shipboard provisions of eighteenth-century Atlantic fishermen. From the PIE root *kelh₁-, through Roman warming-pots and Breton fishing kettles, to the tureens of the Try Pots Inn and the contested chowders of modern Boston, the word has always named the vessel first and the dish second.