- The definition of a parabola is a symmetrical plane curve that forms when a cone intersects with a plane parallel to its side.
A u-shaped graph of a quadratic function is an example of a parabola.
Origin of parabolaModern Latin ; from Classical Greek parabolē, literally , application, comparison (see parable): it is produced by the “application” of a given area to a given straight line
Origin of parabolaNew Latin, from Greek parabolē, comparison, application, parabola (from the relationship between the line joining the vertices of a conic and the line through its focus and parallel to its directrix), from paraballein, to compare; see parable.
Any point on a parabola is the same distance from the directrix as it is from the focus (F). AC equals CF and BD equals DF.
(plural parabolas or parabolae or parabolæ)
- (geometry) The conic section formed by the intersection of a cone with a plane parallel to a tangent plane to the cone; the locus of points equidistant from a fixed point (the focus) and line (the directrix).
- (rhetoric) The explicit drawing of a parallel between two essentially dissimilar things, especially with a moral or didactic purpose. A parable.
From Ancient Greek παραβολή (parabolē), from παραβάλλω (paraballō, “I set side by side”), from παρά (para, “beside”) + βάλλω (ballō, “I throw”).