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decertify

[dee-sur-tuh-fahy]
verb (used with object), de·cer·ti·fied, de·cer·ti·fy·ing.
  1. to withdraw certification from.

Origin of decertify

First recorded in 1915–20; de- + certify
Related formsde·cer·ti·fi·ca·tion [dee-sur-tuh-fuh-key-shuh n, dee-ser-tif-uh-] /diˌsɜr tə fəˈkeɪ ʃən, ˌdi sərˌtɪf ə-/, noun
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for decertify

decertify

verb -fies, -fying or -fied (tr)
  1. to withdraw or remove a certificate or certification from (a person, organization, or country)
Derived Formsdecertification, noun
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