reciprocation

reciprocate +‎ -ion

• Rhymes: -eɪʃən

reciprocation (countable and uncountable, plural reciprocations)

1. The act of reciprocating; interchange of acts; a mutual giving and returning

   the reciprocation of kindness

2. Alternate recurrence or action; as, the reciprocation of the sea in the flow and ebb of tides; oscillation.
   • 1662 Thomas Salusbury, Galileo's Dialogue Concerning the Two Chief World Systems, Dialogue 2:

     ... the same pendulum alwayes maketh its reciprocations in equall times.

• requital
• retaliation

• reciprocation in The Century Dictionary, New York, N.Y.: The Century Co., 1911.
• reciprocation in Webster’s Revised Unabridged Dictionary, G. & C. Merriam, 1913.
• “reciprocation” in The Oxford English Dictionary, 2nd edition, Oxford: Clarendon Press, 1989, →ISBN.