The Collaborative International Dictionary of English v.0.48:

Antiquity \An*tiq"ui*ty\, n.; pl. Antiquities. [L. antiquitas,
   fr. antiquus: cf. F. antiquit['e]. See Antique.]
   1. The quality of being ancient; ancientness; great age; as,
      a statue of remarkable antiquity; a family of great
      antiquity.
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   2. Old age. [Obs.]
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            It not your voice broken? . . . and every part about
            you blasted with antiquity?           --Shak.
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   3. Ancient times; former ages; times long since past; as,
      Cicero was an eloquent orator of antiquity.
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   4. The ancients; the people of ancient times.
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            That such pillars were raised by Seth all antiquity
            has ?vowed.                           --Sir W.
                                                  Raleigh.
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   5. An old gentleman. [Obs.]
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            You are a shrewd antiquity, neighbor Clench. --B.
                                                  Jonson.
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   6. A relic or monument of ancient times; as, a coin, a
      statue, etc.; an ancient institution.

   Note: [In this sense, usually in the plural.] "Heathen
         antiquities." --Bacon.
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WordNet (r) 3.0 (2006):

antiquity
    n 1: the historic period preceding the Middle Ages in Europe
    2: extreme oldness [syn: ancientness, antiquity]
    3: an artifact surviving from the past

Moby Thesaurus II by Grady Ward, 1.0:

79 Moby Thesaurus words for "antiquity":
   abidingness, aboriginality, age, ancien regime, ancient history,
   ancient manuscript, ancient times, ancientness, antique, archaism,
   artifact, atavism, cave painting, cobwebs of antiquity, constancy,
   continuance, defeat of time, defiance of time, distance of time,
   distant past, diuturnity, durability, durableness, duration,
   dust of ages, eld, elderliness, eldership, endurance, eolith,
   fossil, great age, hoary age, hoary eld, inveteracy, lastingness,
   long standing, long-lastingness, long-livedness, longevity,
   maintenance, mezzolith, microlith, neolith, old age, old order,
   old style, oldness, paleolith, perdurability, perennation,
   permanence, perpetuity, persistence, petrification,
   petrified forest, petrified wood, petroglyph, plateaulith,
   primitiveness, primogeniture, primordialism, primordiality, relic,
   reliquiae, remains, remote age, ruin, ruins, senility, seniority,
   stability, standing, steadfastness, survival, survivance,
   time immemorial, venerableness, vestige