The Collaborative International Dictionary of English v.0.48:

Equate \E*quate"\, v. t. [imp. & p. p. Equated; p. pr. & vb.
   n. Equating.] [L. aequatus, p. p. of aequare to make level
   or equal, fr. aequus level, equal. See Equal.]
   To make equal; to reduce to an average; to make such an
   allowance or correction in as will reduce to a common
   standard of comparison; to reduce to mean time or motion; as,
   to equate payments; to equate lines of railroad for grades or
   curves; equated distances.
   [1913 Webster]

         Palgrave gives both scrolle and scrowe and equates both
         to F[rench] rolle.                       --Skeat
                                                  (Etymol. Dict.
                                                  ).
   [1913 Webster]

   Equating for grades (Railroad Engin.), adding to the
      measured distance one mile for each twenty feet of ascent.


   Equating for curves, adding half a mile for each 360
      degrees of curvature.
      [1913 Webster]

WordNet (r) 3.0 (2006):

equate
    v 1: consider or describe as similar, equal, or analogous; "We
         can compare the Han dynasty to the Romans"; "You cannot
         equate success in financial matters with greed" [syn:
         compare, liken, equate]
    2: be equivalent or parallel, in mathematics [syn: equate,
       correspond]
    3: make equal, uniform, corresponding, or matching; "let's
       equalize the duties among all employees in this office"; "The
       company matched the discount policy of its competitors" [syn:
       equal, match, equalize, equalise, equate]

Moby Thesaurus II by Grady Ward, 1.0:

57 Moby Thesaurus words for "equate":
   accommodate, adjust, align, ally, apply, assimilate, associate,
   balance, bind, bracket, cancel, collimate, collineate, compare,
   compensate, connect, consider, coordinate, correlate, correspond,
   counterbalance, counterpoise, countervail, couple, draw a parallel,
   equalize, equidistance, even, even up, fit, follow, hold, identify,
   integrate, interrelate, level, liken, line up, link, match,
   paragon, parallel, parallelize, place parallel to, poise,
   proportion, realign, regard, relate, relativize, represent,
   similize, square, strike a balance, tie, treat, wed