- A set of k points in a plane, such that no three of the points are collinear.
- complete arc
- A k-arc which is not contained in any k+1-arc.
- a.k.a. translation oval, an oval equivalent to one of the form f(x) = x.
- A permutation polynomial, f(x), over GF(q) that satisfies (t - r)(f(t) - f(s))(t - s)(f(t) - f(r)) for all distinct t, s, and r in GF(q).