graticule

 
Pronunciation: /ˈgratɪkjuːl/

noun

technical
  • a network of lines representing meridians and parallels, on which a map or plan can be represented.
  • a series of fine lines or fibres in the eyepiece of an optical device, such as a microscope, or on the screen of an oscilloscope, used as a measuring scale or an aid in locating objects.

Origin:

late 19th century: from French, from medieval Latin graticula 'a little grating', from Latin craticula 'gridiron', diminutive of cratis 'hurdle'