Describing someone who is prudish, strict about morality, or judgmental about others' behavior, especially regarding sexual or social conduct.
From 'bluenose,' originally a term for Nova Scotians (possibly from a potato variety or blue-nosed potatoes from that region), which evolved to mean a puritanical person. The term emerged in North America in the 19th century with its moral connotation by the 1880s.
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