or boart, bortz
low-quality diamond, in granular aggregate or small fragments, valuable only in crushed or powdered form, especially for industrial use as an abrasive.
Origin of bort
1615–25; apparently metathetic variant of *brot (Old English gebrot fragment); akin to Middle English brotel brittle, Old Norse brot fragment
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
boart bortz (bɔːts)
an inferior grade of diamond used for cutting and drilling or, in powdered form, as an industrial abrasive
Word Origin for bort
Old English gebrot fragment; related to Old Norse brot piece, Old High German broz bud
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
"waste diamonds, small chips from diamond-cutting," of unknown origin, perhaps related to Old French bort "bastard."
Online Etymology Dictionary, © 2010 Douglas Harper