An Etymological Dictionary of Astronomy and Astrophysics

A function consisting of several segments, usually → polynomials, joined smoothly together at specific points with an explicitly stated degree of accuracy. Spline functions are used to approximate a given function on an interval.

See also: From East Anglian dialect, maybe related to O.E. splin and to modern splint. A spline was originally a slat or a thin strip of wood. A later meaning was “a long, thin, flexible strip used as a guide for drawing arcs of curves;” → function.