Английский разговорный словарь (основной) - ellipse

ɪˈlɪps n. a regular oval, traced by a point moving in a plane so that the sum of its distances from two other points is constant, or resulting when a cone is cut by a plane which does not intersect the base and makes a smaller angle with the base than the side of the cone makes (cf. HYPERBOLA). [F f. L ellipsus f. Gk elleipsis f. elleipo come short f. en in + leipo leave]