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National Bureau of Standards

noun U.S. Government.
  1. the federal agency that establishes the standards for units used in measuring the physical properties of substances. Abbreviation: NBS, N.B.S.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for national bureau of standards

National Bureau of Standards

noun
  1. (in the US) an organization, founded in 1901, whose function is to establish and maintain standards for units of measurementsCompare British Standards Institution
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