Why is the ninth month called September?
1714, short for doily-napkin (1711), from doily "thin, woolen fabric;" supposedly from Doiley, surname of a 17c.-early 18c. dry-goods dealer on London's Strand. Doily earlier meant "genteel, affordable woolens" (1670s), evidently from the same source. The surname is d'Ouilly, from one of several places called Ouilly in Normandy.