Simple past tense and past participle of credential.(verb)
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Use "credentialed" in a sentence
"The myth that poets and writers attend MFA programs to "professionalize" themselves -- to get "credentialed" -- has been proven false."
"So is that what Dems now call a credentialed reporter asking a tough question?"
"I have been on the road for the past two weeks-first in Denver where I was on staff as a member of the Democratic National Convention's online content team, and more recently in Minneapolis, where I was attending, and blogging, the RNC as special press, aka credentialed new media."