The Collaborative International Dictionary of English v.0.48:

Transact \Trans*act"\, v. t. [imp. & p. p. Transacted; p. pr.
   & vb. n. Transacting.] [L. transactus, p. p. of transigere.
   See Transaction.]
   To carry through; to do; perform; to manage; as, to transact
   commercial business; to transact business by an agent.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Transact \Trans*act"\, v. i.
   To conduct matters; to manage affairs. [R.] --South.
   [1913 Webster]

WordNet (r) 3.0 (2006):

transact
    v 1: conduct business; "transact with foreign governments"

Moby Thesaurus II by Grady Ward, 1.0:

41 Moby Thesaurus words for "transact":
   abide by, accomplish, adhere to, administer, carry on, carry out,
   carry through, complete, conclude, conduct, cope with, deal with,
   discharge, dispatch, dispose of, do, effect, effectuate, enact,
   enforce, execute, fill out, finish, fulfill, handle, honor,
   implement, make, make out, manage, negotiate, observe, perform,
   promulgate, prosecute, put in force, put through, render, settle,
   take care of, transact