"a curve commonly defined as the intersection of a cone with a plane parallel with its side," 1570s, from Modern Latin parabola, from Greek parabole "a comparison, parable," literally "a throwing beside," hence "a juxtaposition" (see parable), so called by Apollonius of Perga c. 210 B.C.E. because it is produced by "application" of a given area to a given straight line. It had a different sense in Pythagorean geometry. Related: Parabolic.
