Given a point with trilinear coordinates P = α:β:γ, the anticevian triangle Δ A' B' C' of a triangle Δ A B C with respect to P is a triangle such that 1.B' C' passes through A, C' A' passes through B, and A' B' passes through C. 2.A A', B B', and C C' pass through P. 3.Δ A B C is the Cevian triangle of Δ A' B' C' with respect to P. The anticevian triangle has trilinear vertex matrix [-α | β | γ α | -β | γ α | β | -γ] (Kimberling 1998, pp. 55 and 185), and is a central triangle of type 1.

Cevian triangle