Why is the ninth month called September?
c.1400, from Old French bedüin (Modern French bédouin), from colloquial Arabic badawin "desert-dwellers," plural of badawi, from badw "desert, camp." The Arabic plural suffix was mistaken for part of the word. A word from the Crusades, it probably was lost in English and then reborrowed from French c.1600. As an adjective from 1844.