1. a bad-tempered, difficult, cantankerous person
"My principal is such a curmudgeon; I'm pretty sure he's jealous of our full heads of hair."
"Without proper caffeine intake in the morning, many adults turn into curmudgeons."
Origin: (from etymonline.com)
"1570s, of unknown origin; the suggestion, based on a misreading of a garbled note from Johnson, that it is from French coeur mechant 'evil heart' is not taken seriously; the first syllable may be cur 'dog.'"
Awkwardness rating: 4