Backsight 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.

Example:
In surveying terms is it spelt Backsight and foresight?

Taxonomy
GAG, Computer Software, Inc, Surveying Software, Continuing Education.

Defination from the web:
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