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Abney level

[ab-nee]
noun Surveying.
  1. a hand level for determining elevations and angles of slope.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for abney level

Abney level

noun
  1. a surveying instrument consisting of a spirit level and a sighting tube, used to measure the angle of inclination of a line from the observer to another point

Word Origin for Abney level

C20: named after Sir William Abney (1843–1920), British chemist and physicist
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012