Bible Dictionaries
Backsight

Webster's Dictionary

(n.) The reading of the leveling staff in its unchanged position when the leveling instrument has been taken to a new position; a sight directed backwards to a station previously occupied. Cf. Foresight, n., 3.

Bibliography Information
Webster, Noah. Entry for 'Backsight'. Noah Webster's American Dictionary. https://www.studylight.org/​dictionaries/​eng/​web/​b/backsight.html. 1828.