One of the mysteries of the English language finally explained.
1figurative, obsolete Made of a type of heavy blue twilled cotton cloth, typically used for work clothes (now usually denim). Also figurative: †dull, plain, ordinary (obsolete).
2Characterized by or wearing blue jeans.
A heavy blue twilled cotton cloth, typically used for work clothes; blue denim.
Early 19th century. From blue + jean. Compare slightly earlier blue jeans.
blue jean/bluː ˈdʒiːn/
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