[1] : The Collaborative International Dictionary of English v.0.48

reciprocally \recip"rocally\ r-esi^p"r-okally^,
   adv.
   1. in a reciprocal manner; so that each affects the other,
      and is equally affected by it; interchangeably; mutually.
      1913 webster

            these two particles do reciprocally affect each
            other with the same force.            --bentley.
      1913 webster

   2. math. in the manner of reciprocals.
      1913 webster

   reciprocally proportional arith.  alg., proportional, as
      two variable quantities, so that the one shall have a
      constant ratio to the reciprocal of the other.
      1913 webster
see also:
reciprocally proportional 

[2] : WordNet (r) 2.0

reciprocally
     adv 1: often followed by `for' in exchange or in reciprocation;
            "gave up our seats on the plane and in return received
            several hundred dollars and seats on the next plane
            out"; "we get many benefits in return for our taxes"
            syn: in return
     2: in a mutual or shared manner; "the agreement was mutually
        satisfactory"; "the goals of the negotiators were not
        reciprocally exclusive" syn: mutually
     3: in an inverse or contrary manner; "inversely related";
        "wavelength and frequency are, of course, related
        reciprocally"- f.a.geldard syn: inversely
see also:
in return mutually inversely 

Reciprocally >> R Words
Reciprocally, definition of term: Reciprocally
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