Churl is a noun that refers to an impolite, mean-spirited person.
Coming from Old English, our word of the day is generally used as an insult. It sometimes means ‘a miser’ or ‘cheap person.’ Or it can simply refer to someone who isn’t polite.
Only a churl could ruin the birthday party of a ten-year-old with impolite behavior. But leave it to the grown-ups to spoil the fun.