instrument used in surveying to measure the height of distant points in relation to a bench mark (a point for which the height above sea level is ... [2 related articles] Found on http://www.britannica.com/eb/a-z/s/191
noun surveying instrument consisting basically of a small telescope with an attached spirit level rotating around a vertical axis; for measuring relative heights of land Found on https://www.encyclo.co.uk/local/20974