#cross_hair__crosshair__cross_wire__crosswire  either of two fine mutually perpendicular lines that cross in the focus plane of an optical instrument and are use for sighting or calibration; "he had the target in his cross hairs"
  supertype:  line_like_mark__line  a mark that is long relative to its width; "He drew a line on the chart"; "The substance produced characteristic lines on the spectroscope"
  part of:  reticle__graticule  a network of fine lines, dots, cross hairs, or wires in the focal plane of the eyepiece of an optical instrument
     part of:  eyepiece__ocular  combination of lenses at the viewing end of optical instruments
        part of:  binocular__fieldglasse__operaglasse  an optical instrument designed for simultaneous use by both eyes
        part of:  light_microscope__lightmicroscope  microscope consisting of an optical instrument that magnifies the image of an object
        part of:  optical_telescope__opticaltelescope  an astronomical telescope designed to collect and record light from cosmic sources
        part of:  sight.optical_instrument  a optical instrument for aiding the eye in aiming, as on a firearm or surveying instrument
           part of:  firearm__piece__small-arm__smallarm  a portable gun; "he wore his firearm in a shoulder holster"
           part of:  surveying_instrument__surveyinginstrument__surveyor's_instrument  an instrument used by surveyors

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