A written communication containing unpleasant material, especially one that criticizes, insults, or intimidates the recipient.(noun)
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Use "nastygram" in a sentence
"Elliott Back's personal site about Cornell University has attracted a nastygram from the university, which argues that it's possible that someone (presumably someone very foolish) might mistake his site (whose URL is cornell. elliottback.com) with Cornell University's site."
"Next a court in Jersey yesterday ruled against Edward Felton, who was intimidated out of publishing an academic paper deconstructing the security model of the Secure Digital Music Initiative by a nastygram from the RIAA."
"This solution was certainly interesting and unique, but of course there are many cases where the nastygram is the best approach."