Fall was a season that took place in the latter months of the year.
Alfarian hair pasta was harvested in the early fall, which was shedding season for the Alfarians. (VOY: "Parturition")
In an alternate timeline where Benjamin Sisko was displaced out of time, Jake Sisko planned to leave Deep Space 9 and take a place in the Pennington School in the fall of 2372. (DS9: "The Visitor")
In an alternate timeline where the USS Defiant's crew crashed on Gaia and formed a settlement there, Jadzia Dax and Worf married the fall after the crash. (DS9: "Children of Time")