The Collaborative International Dictionary of English v.0.48:

Appearance \Ap*pear"ance\, n. [F. apparence, L. apparentia, fr.
   apparere. See Appear.]
   1. The act of appearing or coming into sight; the act of
      becoming visible to the eye; as, his sudden appearance
      surprised me.
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   2. A thing seed; a phenomenon; a phase; an apparition; as, an
      appearance in the sky.
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   3. Personal presence; exhibition of the person; look; aspect;
      mien.
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            And now am come to see . . .
            It thy appearance answer loud report. --Milton.
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   4. Semblance, or apparent likeness; external show. pl.
      Outward signs, or circumstances, fitted to make a
      particular impression or to determine the judgment as to
      the character of a person or a thing, an act or a state;
      as, appearances are against him.
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            There was upon the tabernacle, as it were, the
            appearance of fire.                   --Num. ix. 15.
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            For man looketh on the outward appearance. --1 Sam.
                                                  xvi. 7.
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            Judge not according to the appearance. --John. vii.
                                                  24.
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   5. The act of appearing in a particular place, or in society,
      a company, or any proceedings; a coming before the public
      in a particular character; as, a person makes his
      appearance as an historian, an artist, or an orator.
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            Will he now retire,
            After appearance, and again prolong
            Our expectation?                      --Milton.
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   6. Probability; likelihood. [Obs.]
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            There is that which hath no appearance. --Bacon.
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   7. (Law) The coming into court of either of the parties; the
      being present in court; the coming into court of a party
      summoned in an action, either by himself or by his
      attorney, expressed by a formal entry by the proper
      officer to that effect; the act or proceeding by which a
      party proceeded against places himself before the court,
      and submits to its jurisdiction. --Burrill. --Bouvier.
      --Daniell.
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   To put in an appearance, to be present; to appear in
      person.

   To save appearances, to preserve a fair outward show.
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   Syn: Coming; arrival; presence; semblance; pretense; air;
        look; manner; mien; figure; aspect.
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Moby Thesaurus II by Grady Ward, 1.0:

203 Moby Thesaurus words for "appearance":
   Christophany, Masan, Prospero, Satanophany, accomplishment,
   achievement, acting, advent, affectation, air, airiness,
   angelophany, apparent character, apparition, appearances, approach,
   arrival, aspect, astral, astral spirit, attainment, attitudinizing,
   avatar, banshee, bearing, bluff, bluffing, cheating, color,
   coloring, coming, control, countenance, deception, delusion,
   delusiveness, demeanor, departed spirit, disclosure,
   disembodied spirit, disguise, display, dissemblance, dissembling,
   dissemination, dissimulation, duppy, dybbuk, eidolon, embodiment,
   epiphany, evidence, evincement, expression, exteriority, exteriors,
   external appearance, externality, externalness, externals,
   extrinsicality, facade, face, fakery, faking, fallaciousness,
   false air, false appearance, false front, false image, false light,
   false show, falseness, falsity, fantasy, features, feigning, feint,
   fiction, figure, foreignness, form, four-flushing, fraud, front,
   gaudiness, ghost, gilt, gloss, grateful dead, guide, guise, hant,
   haunt, hint, humbug, humbuggery, idealization, idolum, illusion,
   illusionism, illusionist, illusiveness, image, immateriality,
   imposture, incarnation, incorporeal, incorporeal being,
   incorporeity, indication, larva, lemures, lineaments, look, looks,
   magic, magic act, magic show, magician, make-believe, manes,
   manifestation, manner, masquerade, materialization, mere externals,
   meretriciousness, mien, mirage, oni, openness, ostent, ostentation,
   outerness, outside, outward appearance, outward show, outwardness,
   phantasm, phantasma, phantasmagoria, phantom, phasm, phenomenon,
   playacting, pneumatophany, poltergeist, pose, posing, posture,
   presence, prestidigitation, pretense, pretension, pretext, proof,
   public image, publication, reaching, representation, revelation,
   revenant, seeming, semblance, shade, shadow, shallowness, sham,
   shape, show, showing, shrouded spirit, simulacrum, simulation,
   sleight of hand, sorcerer, sorcery, specious appearance,
   speciousness, specter, spectral ghost, spirit, spook, sprite,
   suggestion, superficiality, surface appearance, surface show,
   theophany, unactuality, unreality, unsubstantiality, vain show,
   varnish, vision, waking dream, walking dead man, wandering soul,
   wildest dream, window dressing, wraith, zombie