triangulation

英 [traɪæŋɡjʊ'leɪʃn] 美[traɪ,æŋɡju'leʃən]

1. a trigonometric method of determining the position of a fixed point from the angles to it from two fixed points a known distance apart; useful in navigation

2. a method of surveying; the area is divided into triangles and the length of one side and its angles with the other two are measured, then the lengths of the other sides can be calculated