One who plagiarizes; or purloins the words, writings, or ideas of another, and passes them off as his or her own; a literary thief; a plagiary.(noun)
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Use "plagiarist" in a sentence
"NB: As an addendum to my last comment (still the last on the page, unless someone comments while I write this), because I've learned in the last few hours that calling Biden a plagiarist is truly unfair, I add the following, which I'm stealing directly from a comment thread at Making Light and I don't know how to do a proper hyperlink:"
"Turns out my plagiarist is taking a class with him too, and Tom starts raving about this Joyce paper the kid wrote."
"And when someone like Stephen Ambrose turns out to be a serial plagiarist, which is what he was from the beginning of his career, as I document in the book, then that pulls down the whole edifice the rest of us are trying to construct whereby people respect us because we follow the rules that we impose upon ourselves."