Definition of surface gauge in US English:

surface gauge

(US surface gage)

noun

  • 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.