A closed curve, the locus of a point such that the sum of the distances from that point to two other fixed points (called the foci of the ellipse) is constant; equivalently, the conic section that is the intersection of a cone with a plane that does not intersect the base of the cone.
User Defined Definitions
"a closed plane curve resulting from the intersection of a circular cone and a plane cutting completely through it"
"omission or suppression of parts of words or sentences"