Niner or Niners may refer to:
Take Me Out to the Holosuite
The baseball team the crewmembers create is called the “Niners“, which in turn became the term for fans of the series.
Assembled to meet a challenge issued by Captain Solok and his team, the Vulcan Logicians of the starship T’Kumbra, the Niners participated in one baseball game in one of DS9′s holosuites. With only team members Benjamin Sisko, his son Jake Sisko and girlfriend Kasidy Yates having any experience with the game, the Niners experience was one of intense training. Benefiting the team were the gymnastic talents of Ezri Dax, the genetically-engineered physical abilities of Julian Bashir and the natural strength of Klingon player Worf, the team nevertheless lost to the Logicians. With both Sisko and Solok ejected from the game by umpire Odo, the Niners scored a single run from Nog, on an accidental (but triumphant) squeeze bunt by Rom. (DS9: “Take Me Out to the Holosuite“)
Niners, eventually became a term for all fans of Deep Space Nine. Like a disassociation from the General Term “Trekkies”, “Niners” is a term adopted by DS9 Fans who believe that Deep Space Nine is the best series of the franchise and many who consider that proclaiming it is a way to isolate themselves from the Trekkie Community, as many are either not fans of Star Trek in general but believe that DS9 is superior to other Trek Series and they do not want to be associated with the franchise as a whole.
The only Niners I know of are Deep Space Nine fans.