triangulation

noun

1. A technique in which distances and directions are estimated from an accurately measured baseline and the principles of trigonometry; an instance of the use of this technique.
2. The network of triangles so obtained, that are the basis of a chart or map.
3. A delaying move in which the king moves in a triangular path to force the advance of a pawn.
4. A subdivision of a planar object into triangles, and by extension the subdivision of a higher-dimension geometric object into simplices.