The Collaborative International Dictionary of English v.0.48:

Appliance \Ap*pli"ance\, n.
   1. The act of applying; application.
      [1913 Webster]

   2. subservience; compliance. [Obs.] --Shak.
      [1913 Webster]

   3. A thing applied or used as a means to an end; an apparatus
      or device; as, to use various appliances; a mechanical
      appliance; a machine with its appliances.
      [1913 Webster]

   4. Specifically: An apparatus or device, usually powered
      electrically, used in homes to perform domestic functions.
      An appliance is often categorized as a major appliance or
      a minor appliance by its cost. Common major appliances are
      the refrigerator, washing machine, clothes drier,
      oven, and dishwasher. Some minor appliances are a
      toaster, vacuum cleaner or microwave oven.
      [PJC]

The Collaborative International Dictionary of English v.0.48:

Dishwasher \Dish"wash`er\, n.
   1. One who, or that which, washes dishes.
      [1913 Webster]

   2. (Zool.) A European bird; the wagtail.
      [1913 Webster]

   3. an electrical appliance[4] which washes tableware
      automatically by directing powerful streams of hot soapy
      water at the items from multiple jets.
      [PJC]

WordNet (r) 3.0 (2006):

dishwasher
    n 1: a machine for washing dishes [syn: dishwasher, dish
         washer, dishwashing machine]
    2: someone who washes dishes

Moby Thesaurus II by Grady Ward, 1.0:

45 Moby Thesaurus words for "dishwasher":
   aquamanile, automatic dishwasher, basin, bath, bathtub, bidet,
   dishpan, dishwiper, dry cleaner, ewer, finger bowl, kitchen sink,
   launderer, laundress, laundryman, laundrywoman, lavabo, lavatory,
   piscina, pot-walloper, scullery maid, scullion, shower,
   shower bath, shower curtain, shower head, shower room,
   shower stall, showers, sink, tub, wash barrel, wash boiler,
   washbasin, washbowl, washdish, washer, washerman, washerwife,
   washerwoman, washing machine, washing pot, washpot, washstand,
   washtub