Source : Webster's Revised Unabridged Dictionary (1913)

Rejection \Re*jec"tion\ (r?-j?k"sh?n), n. [L. rejectio: cf. F.
   r['e]jection.]
   Act of rejecting, or state of being rejected.

Source : WordNet®

rejection
     n 1: the act of rejecting something; "his proposals were met with
          rejection"
     2: the state of being rejected [ant: {acceptance}]
     3: (medicine) an immunological response that refuses to accept
        substances or organisms that are recognized as foreign;
        "rejection of the transplanted liver"
     4: the speech act of rejecting