Why is the ninth month called September?
1660s, American English, probably an alteration of Middle English hurtilbery "whortleberry" (15c.), from Old English horte "whortleberry." Technically the fruit and plant of Gaylussacia, but also widely colloquially applied to the closely related blueberry (Vaccinium). Slang meaning "person of little consequence" is attested from 1835.