Why is the ninth month called September?
1610s, from Middle French recurrent (16c.) and directly from Latin recurrentem (nominative recurrens), present participle of recurrere "run back, hasten back, return" (see recur). From 1590s as a noun ("recurrent muscle").
recurrent re·cur·rent (rĭ-kûr'ənt, -kŭr'-)
Occurring or appearing again or repeatedly.
Turning in a reverse direction. Used of blood vessels and nerves.