From Middle English, borrowed from Old French octobre, from Latin octōber (“eighth month”), from Latin octō (“eight”), from Proto-Indo-European *oḱtṓw (“twice four”); + Latin -ber, from -bris, an adjectival suffix; October was the eighth month in the Roman calendar.

October (plural Octobers)

1. The tenth month of the Gregorian calendar, following September and preceding November. Abbreviation: Oct.
2. (rare) A female given name from English.