Source : Webster's Revised Unabridged Dictionary (1913)

Reciprocally \Re*cip"ro*cal*ly\, adv.
   1. In a reciprocal manner; so that each affects the other,
      and is equally affected by it; interchangeably; mutually.

            These two particles to reciprocally affect each
            other with the same force.            --Bentley.

   2. (Math.) In the manner of reciprocals.

   {Reciprocally proportional} (Arith. & Alg.), proportional, as
      two variable quantities, so that the one shall have a
      constant ratio to the reciprocal of the other.