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.]
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         Expenses in the city were to be economized. --Jowett
                                                  (Thucyd. ).
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         Calculating how to economize time.       --W. Irving.
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