- black sheep (n.)
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- by 1822 in figurative sense of "member of some group guilty of offensive conduct and unlike the other members," supposedly because a real black sheep had wool that could not be dyed and was thus worth less. But one black sheep in a flock was considered good luck by shepherds in Sussex, Somerset, Kent, Derbyshire. Baa Baa Black Sheep nursery rhyme's first known publication is in "Tommy Thumb's Pretty Song Book" (c. 1744).