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Frenkel defect

British  
/ ˈfrɛnkəl /

noun

  1. physics a crystal defect in which a lattice ion has moved to an interstitial position leaving a vacant lattice site

"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 Frenkel defect

C20: named after I. I. Frenkel (1894–1952), Russian physicist