The Collaborative International Dictionary of English v.0.48:

Sauce \Sauce\, n. [F., fr. OF. sausse, LL. salsa, properly, salt
   pickle, fr. L. salsus salted, salt, p. p. of salire to salt,
   fr. sal salt. See Salt, and cf. Saucer, Souse pickle,
   Souse to plunge.]
   1. A composition of condiments and appetizing ingredients
      eaten with food as a relish; especially, a dressing for
      meat or fish or for puddings; as, mint sauce; sweet sauce,
      etc. "Poignant sauce." --Chaucer.
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            High sauces and rich spices fetched from the Indies.
                                                  --Sir S.
                                                  Baker.
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   2. Any garden vegetables eaten with meat. [Prov. Eng. &
      Colloq. U.S.] --Forby. Bartlett.
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            Roots, herbs, vine fruits, and salad flowers . . .
            they dish up various ways, and find them very
            delicious sauce to their meats, both roasted and
            boiled, fresh and salt.               --Beverly.
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   3. Stewed or preserved fruit eaten with other food as a
      relish; as, apple sauce, cranberry sauce, etc. [U.S.]
      "Stewed apple sauce." --Mrs. Lincoln (Cook Book).
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   4. Sauciness; impertinence. [Low.] --Haliwell.
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   To serve one the same sauce, to retaliate in the same kind.
      [Vulgar]
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