Definition of blue plate in English:

blue plate

adjective

North american
  • [attributive] (of a restaurant meal) consisting of a full main course ordered as a single menu item.

    • ‘These are basically the blue-plate special of Japan, in which you get, along with your entrée, soup, salad, rice, and a few little pickles.’
    • ‘You'd be amazed what happens at the diner, a blue-plate special restaurant in an industrial district near the airport.’
    • ‘The restaurant features 20 different beef and bison burgers, blue-plate specials, beef filets, salads and roasted ‘beer can chicken;’ plus cedar-planked steelhead salmon.’
    • ‘It's homier and more idiosyncratic than most of Houston's Middle Eastern spots, with a rich human scene and numerous unexpected dishes, thanks to a slate of daily blue-plate specials.’
    • ‘Those soothing ‘diner’ colors of turquoise, black and pink serve as the backdrop for this blue-plate special of coolness.’
    • ‘Diners that serve a standard menu of coffee, burgers, fries and blue-plate specials offer comfy booths along with their comfort food.’

Origin

With reference to the original blue plates divided into compartments, on which fixed-price restaurant meals were served.