The Collaborative International Dictionary of English v.0.48:

Resignation \Res`ig*na"tion\ (r[e^]z`[i^]g*n[=a]"sh[u^]n), n.
   [F. r['e]signation. See Resign.]
   1. The act of resigning or giving up, as a claim, possession,
      office, or the like; surrender; as, the resignation of a
      crown or commission.
      [1913 Webster]

   2. The state of being resigned or submissive; quiet or
      patient submission; unresisting acquiescence; as,
      resignation to the will and providence of God.
      [1913 Webster]

   Syn: Patience; surrender; relinquishment; forsaking;
        abandonment; abdication; renunciation; submission;
        acquiescence; endurance. See Patience.
        [1913 Webster]

WordNet (r) 3.0 (2006):

resignation
    n 1: acceptance of despair [syn: resignation, surrender]
    2: the act of giving up (a claim or office or possession etc.)
    3: a formal document giving notice of your intention to resign;
       "he submitted his resignation as of next month"