Definition of surface gauge in English:
surface gauge
noun
(US surface gage)
1A rain gauge situated at ground level, specifically one with an opening flush with the ground.
2Engineering
A gauge for scribing straight lines on a workpiece or checking the height of a point on it, typically consisting of an adjustable scriber mounted on a stand.
Origin
Mid 19th century; earliest use found in Proceedings of the Royal Society of Edinburgh.
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