[trahy-lat-uh-rey-shuh
n] 
| a method of determining the relative positions of three or more points by treating these points as vertices of a triangle or triangles of which the angles and sides can be measured. |
| Main Entry: | trilateration |
| Part of Speech: | n |
| Definition: | a method of surveying in which triangle sides are measured, usually by electronic means; cf. triangulation |
| Etymology: | tri 'triangle' + latus 'side' + -ation |
trilateration
method of surveying in which the lengths of the sides of a triangle are measured, usually by electronic means, and, from this information, angles are computed. By constructing a series of triangles adjacent to one another, a surveyor can obtain other distances and angles that would not otherwise be measurable. Formerly, trilateration was little used in comparison to triangulation, a method for determining two sides and an angle of a triangle from the length of one side and two angles, because of the difficulty of the computations involved. But the development of electronic distance-measuring devices has made trilateration a common and preferred system. Except that only lines are measured, while all angles are computed, the field procedures for trilateration are like those for triangulation.
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