The Collaborative International Dictionary of English v.0.48:

Suitor \Suit"or\, n.
   1. One who sues, petitions, or entreats; a petitioner; an
      applicant.
      [1913 Webster]

            She hath been a suitor to me for her brother.
                                                  --Shak.
      [1913 Webster]

   2. Especially, one who solicits a woman in marriage; a wooer;
      a lover. --Sir P. Sidney.
      [1913 Webster]

   3.
      (a) (Law) One who sues or prosecutes a demand in court; a
          party to a suit, as a plaintiff, petitioner, etc.
      (b) (O. Eng. Law) One who attends a court as plaintiff,
          defendant, petitioner, appellant, witness, juror, or
          the like.
          [1913 Webster]

WordNet (r) 3.0 (2006):

suitor
    n 1: a man who courts a woman; "a suer for the hand of the
         princess" [syn: suitor, suer, wooer]

Moby Thesaurus II by Grady Ward, 1.0:

72 Moby Thesaurus words for "suitor":
   accessory, accusant, accuser, addict, admirer, adorer, allegator,
   amorist, appellant, applicant, asker, aspirant, aspirer, beau,
   beggar, bidder, boyfriend, candidate, cavalier, claimant,
   collector, complainant, coveter, defendant, delator, desirer,
   devotee, escort, fancier, follower, freak, gallant, hankerer,
   hopeful, impeacher, impugner, inamorato, indictor, infatuate,
   informer, libelant, litigant, litigationist, litigator, lover, man,
   panel, paramour, parties litigant, party, petitioner, plaintiff,
   postulant, prayer, prosecutor, pursuer, seeker, solicitant,
   solicitor, spark, sparker, suppliant, supplicant, supplicator,
   swain, the prosecution, votary, wanter, wisher, witness, wooer,
   yearner



Bouvier's Law Dictionary, Revised 6th Ed (1856):

SUITOR. One who is a party to a suit or action in court. One who is a party
to an action. In its ancient sense, suitor meant one Who was bound to attend
the county court, also, one who formed part of the secta. (q.v.)