Source : Webster's Revised Unabridged Dictionary (1913)

Reciprocation \Re*cip`ro*ca"tion\, n. [L. reciprocatio: cf. F.
   reciprocation.]
   1. The act of reciprocating; interchange of acts; a mutual
      giving and returning; as, the reciprocation of kindness.

   2. Alternate recurrence or action; as, the reciprocation of
      the sea in the flow and ebb of tides. --Sir T. Browne.

Source : WordNet®

reciprocation
     n 1: the act of making and return or doing something in return
     2: alternating back-and-forth movement
     3: mutual interaction; the activity of interchanging or
        reciprocating [syn: {interchange}, {give-and-take}]