The Collaborative International Dictionary of English v.0.48:

Olein \O"le*in\ ([=o]"l[-e]*[i^]n), n. [L. oleum oil: cf. F.
   ol['e]ine.] (Physiol. Chem.)
   A fat, liquid at ordinary temperatures, but solidifying at
   temperatures below 0[deg] C., found abundantly in both the
   animal and vegetable kingdoms (see Palmitin). It dissolves
   solid fats, especially at 30-40[deg] C. Chemically, olein is
   a glyceride of oleic acid; and, as three molecules of the
   acid are united to one molecule of glycerol to form the fat,
   it is technically known as triolein. It is also called
   elain.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Elaine \E*la"ine\, or Elain \E*la"in\, n. [Gr. ? olive oil, oil,
   from ? the olive tree: cf. F. ['e]la["i]ne.] (Chem.)
   Same as Olein.
   [1913 Webster]