noun Surveying, Navigation.
a technique for establishing the distance between any two points, or the relative position of two or more points, by using such points as vertices
of a triangle or series of triangles, such that each triangle has a side of known or measurable length (base or base line)
that permits the size of the angles of the triangle and the length of its other two sides to be established by observations taken either upon or from the two ends of the base line.
the triangles thus formed and measured.
< Medieval Latin triangulātiōn-
(stem of triangulātiō
) the making of triangles. See triangulate