cross hair

or cross·hair

noun Usually cross hairs.
  1. Also called cross wire. one of the fine wires or fibers, strands of spider web, or the like, crossing in a focal plane of an optical instrument to center a target or object or to define a line of sight.
  2. one of the marks that aid in the positioning of overlaying images for correct registration in printing.Compare register(def 11b).
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

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