The Collaborative International Dictionary of English v.0.48:

oddity \odd"i*ty\ ([o^]d"[i^]*t[y^]), n.; pl. Oddities
   ([o^]d"[i^]*t[i^]z).
   1. The quality or state of being odd; singularity; queerness;
      peculiarity; as, oddity of dress, manners, and the like.
      [1913 Webster]

            That infinitude of oddities in him.   --Sterne.
      [1913 Webster]

   2. That which is odd; as, a collection of oddities.
      [1913 Webster]

WordNet (r) 3.0 (2006):

oddity
    n 1: eccentricity that is not easily explained [syn: oddity,
         oddness]
    2: a strange attitude or habit [syn: oddity, queerness,
       quirk, quirkiness, crotchet]
    3: something unusual -- perhaps worthy of collecting [syn:
       curio, curiosity, oddity, oddment, peculiarity,
       rarity]