graticule

n. lines that represent parallels of longitude and latitude on maps and globes; network of lines placed in the focal plane of an eyepiece of an optical device (for visual guidance)

A geographic coordinate system enables every location on the earth to be specified by the three coordinates of a spherical coordinate system aligned with the spin axis of the Earth.
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Noun
1. a network of fine lines, dots, cross hairs, or wires in the focal plane of the eyepiece of an optical instrument
(synonym) reticle, reticule
(hypernym) network
(part-holonym) eyepiece, ocular
(part-meronym) cross hair, cross wire

(n.)
A design or draught which has been divided into squares, in order to reproduce it in other dimensions.
  

1. In cartography, a network of lines representing the earth's parallels of latitude and meridians of longitude. 2. In imagery interpretation; See reticle. See also neatlines. 1/11/77