a particular nonparametric estimator of a function

a piecewise cubic polynomial such that the function, its derivative and its second derivative are continuous at the interpolation nodes

a piecewise cubic polynomial with the function value, first derivative, and second derivative being continuous at each interior knot

a segmented function consisting

a smooth (derivatives exist), but piecewise, cubic polynomial that passes through a set of specified points

a spline constructed of piecewise third-order polynomials which pass through a set of control points

A real function constructed by piecing together cubic polynomials on consecutive intervals.