The Collaborative International Dictionary of English v.0.48:

Transaction \Trans*ac"tion\, n. [L. transactio, fr. transigere,
   transactum, to drive through, carry through, accomplish,
   transact; trans across, over + agere to drive; cf. F.
   transaction. See Act, Agent.]
   1. The doing or performing of any business; management of any
      affair; performance.
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   2. That which is done; an affair; as, the transactions on the
      exchange.
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   3. (Civil Law) An adjustment of a dispute between parties by
      mutual agreement.
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   Transaction of a society, the published record of what it
      has done or accomplished.
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   Syn: Proceeding; action; process.

   Usage: Transaction, Proceeding. A transaction is
          something already done and completed; a proceeding is
          either something which is now going on, or, if ended,
          is still contemplated with reference to its progress
          or successive stages.
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   Note: " We the word proceeding in application to an affray in
         the street, and the word transaction to some commercial
         negotiation that has been carried on between certain
         persons. The proceeding marks the manner of proceeding,
         as when we speak of the proceedings in a court of law.
         The transaction marks the business transacted; as, the
         transactions on the Exchange." --Crabb.
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