triangulate
verb geography, mathematics specialized uk/traɪˈæŋ.ɡjə.leɪt/ us/traɪˈæŋ.ɡjə.leɪt/
[ T ]（为进行测量或绘制地图而）把…分成三角形
to divide an area into triangles in order to measure it or draw a map of it
[ I or T ]用三角学求出;用三角测量法测绘（或测定）
to calculate positions and distances using triangles, where some information about the length of sides and size of angles is known