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bondstone

American  
[bond-stohn] / ˈbɒndˌstoʊn /

noun

  1. a stone, as a perpend, for bonding bond facing masonry to a masonry backing.


bondstone British  
/ ˈbɒndˌstəʊn /

noun

  1. Also called: bonder.  a long stone or brick laid in a wall as a header

"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

Etymology

Origin of bondstone

First recorded in 1835–45; bond 1 + stone