A person who aggressively sets out to ruin the Christmas holidays for others.(noun)
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Use "grinch" in a sentence
"Also, astute readers will notice that my list contains no mention of a certain grinch."
"Staffer labelled 'grinch' over Xmas memo A DEPARTMENTAL officer was a "grinch" for writing a memo suggesting Centrelink and Medicare offices should not display nativity scenes at"
"This article ( "Sarah Palin, Dem greens 'grinch" -- POLITICO. com) nicely illustrates the Left's efforts to distract from the damning -- absolutely damning, revelations that leading global warming "scientists" were relying on deception and intimidation to promote their environmental agenda."