The Collaborative International Dictionary of English v.0.48:

Majority \Ma*jor"i*ty\, n.; pl. Majorities. [F. majorit['e].
   See Major.]
   1. The quality or condition of being major or greater;
      superiority. Specifically:
      (a) The military rank of a major.
      (b) The condition of being of full age, or authorized by
          law to manage one's own affairs.
          [1913 Webster]

   2. The greater number; more than half; as, a majority of
      mankind; a majority of the votes cast.
      [1913 Webster]

   3. [Cf. L. majores.] Ancestors; ancestry. [Obs.]
      [1913 Webster]

   4. The amount or number by which one aggregate exceeds all
      other aggregates with which it is contrasted; especially,
      the number by which the votes for a successful candidate
      exceed those for all other candidates; as, he is elected
      by a majority of five hundred votes. See Plurality.
      [1913 Webster]

   To go over to the majority or To join the majority, to
      die.
      [1913 Webster]

WordNet (r) 3.0 (2006):

majority
    n 1: the property resulting from being or relating to the
         greater in number of two parts; the main part; "the
         majority of his customers prefer it"; "the bulk of the work
         is finished" [syn: majority, bulk] [ant: minority]
    2: (elections) more than half of the votes [syn: majority,
       absolute majority]
    3: the age at which persons are considered competent to manage
       their own affairs [syn: majority, legal age] [ant:
       minority, nonage]