The Collaborative International Dictionary of English v.0.48:

Economize \E*con"o*mize\ ([-e]*k[o^]n"[-o]*m[imac]z), v. t.
   [imp. & p. p. Economized ([-e]*k[o^]n"[-o]*m[imac]zd); p.
   pr. & vb. n. Economizing.] [Cf. F. ['e]conomiser.]
   To manage with economy; to use with prudence; to expend with
   frugality; as, to economize one's income. [Written also
   economise.]
   [1913 Webster]

         Expenses in the city were to be economized. --Jowett
                                                  (Thucyd. ).
   [1913 Webster]

         Calculating how to economize time.       --W. Irving.
   [1913 Webster]

Moby Thesaurus II by Grady Ward, 1.0:

36 Moby Thesaurus words for "economizing":
   Scotch, canny, careful, chary, cheeseparing, conserving, cooling,
   cooling down, cooling off, curtailment, cutback, economic,
   economization, forehanded, frugal, labor-saving, low growth rate,
   money-saving, parsimonious, penny-wise, provident, prudent,
   prudential, reduction of expenses, reduction of spending,
   retrenchment, saving, scraping, scrimping, skimping, slowdown,
   spare, sparing, thrifty, time-saving, unwasteful