You needn’t be a linguist to note changes in the language of menus, but Stanford’s Dan Jurafsky has written a book doing just that. In The Language of Food: A Linguist Reads the Menu, Jurafsky describes how he and some colleagues analyzed a database of 6,500 restaurant menus describing 650,000 dishes from across the U.S. Among their findings: fancy restaurants, not surprisingly, use fancier—and longer—words than cheaper restaurants do (think accompaniments and decaffeinated coffee, not sides and decaf). Jurafsky writes that “every increase of one letter in the average length of words describing a dish is associated with an increase of 69 cents in the price of that dish.” Compared with inexpensive restaurants, the expensive ones are “three times less likely to talk about the diner’s choice” (your way, etc.) and “seven times more likely to talk about the chef’s choice.”
Lower-priced restaurants, meanwhile, rely on “linguistic fillers”: subjective words like delicious, flaky, and fluffy. These are the empty calories of menus, less indicative of flavor than of low prices. Cheaper establishments also use terms like ripe and fresh, which Jurafsky calls “status anxiety” words. Thomas Keller’s Per Se, after all, would never use fresh—that much is taken for granted—but Subway would. Per Se does, however, engage in the trendy habit of adding provenance to descriptions of ingredients (Island Creek oysters, Frog Hollow’s peaches). According to Jurafsky, very expensive restaurants “mention the origins of the food more than 15 times as often as inexpensive restaurants.”

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To charge what fine dining establishments charge, it's not enough to source the best ingredients, even though anyone who's peeked at the ledger for a high end restaurant knows the ingredients are a massive cost. Diners expect an experience now, and using more ornate language to describe a dish and the provenance of its ingredients is just as important as beautiful plating and presentation in leaving diners satisfied after having left them several pounds heavier but several hundred dollars lighter.