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]

WordNet (r) 3.0 (2006):

appliance
    n 1: a device or control that is very useful for a particular
         job [syn: appliance, contraption, contrivance,
         convenience, gadget, gizmo, gismo, widget]
    2: durable goods for home or office use

Moby Thesaurus II by Grady Ward, 1.0:

131 Moby Thesaurus words for "appliance":
   Charlie McCarthy, accommodation, accouterments, active use,
   advantage, agent, amenity, ancilla, apparatus, appliances,
   application, appointments, appurtenance, appurtenances, armament,
   brassware, chinaware, clayware, consumption, contrivance,
   convenience, conveniences, copperware, creature, device,
   dinnerware, drive, duffel, dummy, dupe, durable goods, durables,
   earthenware, employ, employment, enamelware, equipage, equipment,
   exercise, exertion, facilities, facility, fittings, fixture,
   fixtures, flatware, furnishings, furniture, gear, glassware,
   go-between, good use, graniteware, handmaid, handmaiden,
   hard goods, hard usage, hard use, hardware, hollow ware,
   housefurnishings, housewares, ill use, impedimenta, implement,
   installations, instrument, interagent, intermediary, intermediate,
   intermedium, ironmongery, ironware, kit, kitchenware, lever,
   machine, machinery, materiel, mechanical aid, mechanical device,
   mechanism, mediator, medium, metalware, midwife, minion, misuse,
   motive power, motor, munition, munitions, operation, organ, outfit,
   ovenware, paraphernalia, pawn, plant, play, plaything, plumbing,
   power plant, power source, puppet, rig, rigging, rough usage,
   servant, silverware, slave, sporting goods, stock-in-trade,
   stoneware, stooge, tableware, tackle, things, tinware, tool,
   tools and machinery, toy, usage, use, using up, utensils, utility,
   vehicle, white goods, woodenware, wrong use