Hors d'oeuvre literally means a dish that sits outside the work
In seventeenth-century France, dinner arrived all at once in rigid symmetry, and the little extra plates set beyond that formal arrangement earned the name hors d'oeuvre. Romans nibbled olives and stuffed dormice before their main courses, and Prohibition's end in America turned the appetiser into a snack carried around on trays.
Small bites before a meal are old. Romans opened dinner with a course called gustatio or promulsis, offering fish, cheeses, olives and even stuffed dormice, while Greeks called their equivalent propoma. The Babylonian Talmud, around 500 AD, describes giving a weakened person something sweet before the main dish to revive the appetite. A few food historians trace the modern habit to Russia, where travellers were greeted with fish, caviar and cured meats, and relatives of the idea include zakuski, the smorgasbord, mezze and antipasto.
The French term grew out of banquet choreography. Medieval hosts served entremets between courses, sometimes food and sometimes spectacle, from butter sculptures to musical performances. When service a la francaise laid every dish out at once, small extras placed beyond the central symmetrical spread became hors d'oeuvres, often a canape of toasted bread with something savoury on top. Francois Massialot first recorded the term in 1691, calling them dishes added beyond what a feast would normally include. Chef Edouard Nignon later claimed they came from Asia and that the French saw them as superfluous to a well-cooked meal.
Britain went its own way. Victorian and Edwardian diners preferred a savoury course near the end of dinner, as a palate cleanser before drinking, such as oysters wrapped in bacon or Scotch woodcock, scrambled egg on toast spread with Gentleman's Relish. That made a starter seem unnecessary. The word appetiser appeared in both the United States and England in 1860, and pre-dinner drinks spread late in the century, when the British began copying French starters.
America's cocktail party finished the transformation. Before the First World War, guests walked straight into the dining room; after Prohibition ended, hosts offered many small dishes to soften stronger drinks, and the appetiser moved from table to circulating tray. Professional kitchens still prepare them in a cool room called the garde manger, and etiquette holds that they should never give away what the main course will be.
Source: Hors d'oeuvre