The Collaborative International Dictionary of English v.0.48:

Reciprocity \Rec`i*proc"i*ty\ (r[e^]s`[i^]*pr[o^]s"[i^]*t[y^]),
   n. [Cf. F. r['e]ciprocit['e]. See Reciprocal.]
   1. Mutual action and reaction.
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   2. Reciprocal advantages, obligations, or rights;
      reciprocation.
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   Reciprocity treaty, or Treaty of reciprocity, a treaty
      concluded between two countries, conferring equal
      privileges as regards customs or charges on imports, or in
      other respects.
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   Syn: Reciprocation; interchange; mutuality.
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