backsight

Plural: backsights

Noun

• The rear sight of a firearm.
• A measurement or reading taken back towards a point of known elevation, used to calculate the height of the surveying instrument (theodolite, transit, total station).
• A measurement of a previously shot point, used to set the angle to zero when occupying a new position.

Verb

• To shoot a backsight.

Related Words

foresight, hindsight