- the tenth month of the year, containing 31 days. Abbreviation: Oct.
- British. ale or beer traditionally brewed in this month.
- the tenth month of the year, consisting of 31 days
c.1050, from Latin October (mensis), from octo “eight,” from PIE root *octo(u)- “eight” (see eight). Eighth month of the old Roman calendar (pre-46 B.C.E.), which began the year in March. For -ber see December. Replaced Old English winterfylleð. In Russian history, October Revolution (in which the Bolsheviks overthrew the Provisional Government) happened Nov. 7, but because Russia had not at that time adpoted the Gregorian calendar reform, this date was reckoned there (Old Style) as Oct. 25.