convexo-concave Hear it!

convexo-concave Definition

convexo-concave (kän vek′sō kän kāv, kən-)

adjective

  1. convex on one side and concave on the other
  2. Optics designating a lens whose convex face has a greater degree of curvature than its concave face, so that the lens is thickest in the middle