- Parabola by Great Soviet Encyclopedia
a curve that is the intersection of a circular cone by a plane parallel to a tangent plane to the...
- Directrix by Webster's
(n.) A line along which a point in another line moves or which in any way governs the motion of the...
- focus by WordNet
nounThe concentration of attention or energy on something.usage: "the focus of activity...
- parabola by Johnathan Hansen
Plane curve consisting of all points equidistant from a given fixed point (focus) and a given fixed...
- focused by WordNet
verbDirect one's attention on something.usage: "Please focus on your studies and not on your...