Past tense of carp; complained or criticized in a nagging, fault-finding manner about something minor.
From carp, which comes from Old Norse 'karpa' meaning 'to brag' or 'to boast,' which evolved into Middle English meaning to talk or complain. The sense shifted from boasting to complaining by the 15th century.
It's fascinating that 'carp' originally meant to brag but shifted to mean complaining—it's like the Vikings had a word for people who wouldn't stop talking, and English speakers decided it fit better with fault-finding than boasting!
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