Source : Webster's Revised Unabridged Dictionary (1913)

Oleomargarine \O`le*o*mar"ga*rine\, n. [L. oleum oil + E.
   margarine, margarin.] [Written also {oleomargarin}.]
   1. A liquid oil made from animal fats (esp. beef fat) by
      separating the greater portion of the solid fat or
      stearin, by crystallization. It is mainly a mixture of
      olein and palmitin with some little stearin.

   2. An artificial butter made by churning this oil with more
      or less milk.

   Note: Oleomargarine was wrongly so named, as it contains no
         margarin proper, but olein, palmitin, and stearin, a
         mixture of palmitin and stearin having formerly been
         called margarin by mistake.

Source : WordNet®

oleomargarine
     n : a spread made chiefly from vegetable oils and used as a
         substitute for butter [syn: {margarine}, {margarin}, {oleo},
          {marge}]