The Collaborative International Dictionary of English v.0.48:

Cession \Ces"sion\, n. [L. cessio, fr. cedere to give way: cf.
   F. Cession. See Cede.]
   1. A yielding to physical force. [Obs.] --Bacon.
      [1913 Webster]

   2. Concession; compliance. [Obs.]
      [1913 Webster]

   3. A yielding, or surrender, as of property or rights, to
      another person; the act of ceding.
      [1913 Webster]

            A cession of the island of New Orleans. --Bancroft.
      [1913 Webster]

   4. (Eccl. Law) The giving up or vacating a benefice by
      accepting another without a proper dispensation.
      [1913 Webster]

   5. (Civil Law) The voluntary surrender of a person's effects
      to his creditors to avoid imprisonment.
      [1913 Webster]

Moby Thesaurus II by Grady Ward, 1.0:

88 Moby Thesaurus words for "cession":
   abalienation, abandonment, abdication, abjuration, abjurement,
   alienation, allowance, amortization, amortizement, assignation,
   assignment, bargain and sale, barter, bequeathal, capitulation,
   circumscription, concession, conferment, conferral, consignation,
   consignment, conveyance, conveyancing, deeding, deliverance,
   delivery, demise, dispensation, disposal, disposition,
   dropping out, dumping, enfeoffment, exception, exchange, exemption,
   extenuating circumstances, forgoing, forswearing, getting rid of,
   giving, giving in, giving over, giving up, grain of salt, grant,
   handing over, hedge, hedging, lease and release, letting go,
   limitation, mental reservation, modification, qualification,
   recantation, recedence, recession, release, relinquishment,
   renouncement, renunciation, reservation, resignation, restriction,
   retraction, retreat, riddance, sacrifice, sale, salvo, settlement,
   settling, special case, special treatment, specialness,
   specification, surrender, swearing off, trading, transfer,
   transference, transmission, transmittal, vesting, waiver,
   withdrawing, yielding