map reference

prominent feature on a map used as a point of reference in navigation

Grid references define locations on maps using grid values. Grid lines on maps define the coordinate system, and are numbered to provide a unique reference to features.Grid systems vary, but the most common is a square grid with grid lines numbered sequentially from the origin at the bottom left of the map. The grid numbers on the east-west (horizontal) axis are called Eastings, and the grid numbers on the north-south (vertical) axis are called Northings.Grids may be arbitrary, or based on specific distances, for example the United Kingdom Ordnance Survey maps use a one kilometre square grid spacing.
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A means of identifying a point on the surface of the earth by relating it to information appearing on a map, generally the graticule or grid. 1/8/79

Identification d'un point à la surface terrestre grâce à des renseignements apparaissant sur une carte, généralement le réseau géographique ou le quadrillage. 1/8/79