The Collaborative International Dictionary of English v.0.48:
Oval \O"val\, n.
A body or figure in the shape of an egg, or popularly, of an
Cassinian oval (Geom.), the locus of a point the product of
whose distances from two fixed points is constant; -- so
called from Cassini, who first investigated the curve.
Thus, in the diagram, if P moves so that P A.P B is
constant, the point P describes a Cassinian oval. The
locus may consist of a single closed line, as shown by the
dotted line, or of two equal ovals about the points A and
[1913 Webster] Ovalbumin