- ellipseA 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.
- ellipsisA mark consisting of multiple full stops (with or without spaces), used to indicate omitted, missing, or illegible words; or (in mathematics) that a pattern continues.