Word Study
backsight
CIDE DICTIONARY
backsight, n. [Back, adv. + sight.].
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. [1913 Webster]
OXFORD DICTIONARY
backsight, n.
1 the sight of a rifle etc. that is nearer the stock.
2 Surveying a sight or reading taken backwards or towards the point of starting.
1 the sight of a rifle etc. that is nearer the stock.
2 Surveying a sight or reading taken backwards or towards the point of starting.
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