What does crosshair mean?
A crosshair is one of a pair of fine, hair-thin lines that cross at right angles in the centre of an optical instrument's field of view. Found in telescopic gunsights, surveying equipment, microscopes, and camera viewfinders, crosshairs give the user a precise reference point for aiming, centring, or measuring whatever lies under them. The term derives from the resemblance of these fine wires or etched lines to hairs, combined with their crossing arrangement. Beyond its literal use, the word carries strong figurative weight: to say a person, company, or issue is 'in the crosshairs' means they are the focus of intense scrutiny, criticism, or attack — a metaphor borrowed directly from the experience of a target framed by a sniper's scope. The plural form 'crosshairs' is standard, and the word appears frequently in military, sporting, scientific, and gaming vocabulary, making it a compact and vivid term for precision, focus, and targeted attention.
nounEither of two fine lines crossing at right angles at the centre of an optical instrument such as a gunsight or microscope, used for precise aiming or locating; more generally, the marked point at the centre of a display or reticle where the lines intersect.
- A pair of fine perpendicular lines at the centre of an optical instrument (gunsight, telescope, microscope) used for precise aiming or positioning.
- By extension, the central aiming point or marker in any sighting device, graphical interface, or targeting display.
"The sniper adjusted his scope until the target sat squarely on the crosshair."
"Through the microscope, she aligned the specimen with the crosshair before taking the measurement."
"In the video game, a red crosshair appears whenever an enemy enters your line of sight."
The plural is the standard form when referring to the pair of lines collectively, and it is the form used in the figurative idiom 'in the crosshairs'. The singular 'crosshair' denotes one of the two lines individually.
"The technician adjusted the crosshairs of the theodolite before taking the reading."
The phrase 'in the crosshairs' has escaped the rifle scope entirely — politicians, companies, and even diseases are now routinely described as being in someone's crosshairs.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of crosshair
The word 'crosshair' is a straightforward English compound of 'cross', referring to the intersecting perpendicular lines, and 'hair', referring to the extremely fine threads originally used as sighting lines in optical instruments. Early telescopic sights employed actual spider silk or fine wire stretched across the lens, which is why 'crosswires' was long an alternative name. The compound arose in the context of firearms optics, likely in the nineteenth century as riflescopes became practical. The root 'cross' itself traces back through Old English 'cros' to Latin 'crux', giving the word a distant kinship with terms like 'crucial' and 'crucify'.
How crosshair is actually used
Almost always used in technical or figurative contexts relating to aiming, targeting, or precision. The plural form 'crosshairs' is standard when referring to the two lines together, and the figurative idiom is almost always plural ('in the crosshairs'). Neutral to slightly formal register; common in military, sporting, scientific, and gaming contexts.
Easily confused with crosshair
A reticle is the entire network of markings in an optical sight, of which the crosshair is just one common design.
A crosswalk is a designated pedestrian crossing on a road, unrelated to aiming devices despite the shared word 'cross'.