triangulation

[ trahy-ang-gyuh-ley-shuh n ]
/ traɪˌæŋ gyəˈleɪ ʃən /

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.

Origin of triangulation

1810–20; < Medieval Latin triangulātiōn- (stem of triangulātiō) the making of triangles. See triangulate, -ion
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

triangulation

/ (traɪˌæŋɡjʊˈleɪʃən) /

noun

a method of surveying in which an area is divided into triangles, one side (the base line) and all angles of which are measured and the lengths of the other lines calculated trigonometrically
the network of triangles so formed
the fixing of an unknown point, as in navigation, by making it one vertex of a triangle, the other two being known
chess a key manoeuvre in the endgame in which the king moves thrice in a triangular path to leave the opposing king with the move and at a disadvantage
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

triangulation

[ trī-ăng′gyə-lāshən ]

A method of determining the relative positions of points in space by measuring the distances, and sometimes angles, between those points and other reference points whose positions are known. Triangulation often involves the use of trigonometry. It is commonly used in the navigation of aircraft and boats, and is the method used in the Global Positioning System , in which the reference points are satellites.