Answer: NINER
NINER is a crossword puzzle answer that we have spotted 106 times.
    - Certain San Franciscan
 
    - Number in NASA-speak
 
    - Frisco gridder
 
    - Frisco footballer
 
    - San Francisco footballer, briefly
 
    - 3Com Park player
 
    - Forty-___
 
    - West Coast gridder
 
    - Bayside footballer
 
    - Ram rival
 
    - Montana, once
 
    - CBer's number
 
    - Eighty-___ (early Oklahoma homesteader)
 
    - Montana, e.g., once
 
    - Montana, notably
 
    - Astronaut's digit
 
    - Number in C.B. lingo
 
    - Cowboy rival
 
    - Bronc rival
 
    - Forty-___ (gold rush participant)
 
    - Joe Montana or Jerry Rice, informally
 
    - Gold Rush figure, for short
 
    - Forty-___ (prospector)
 
    - NFCer
 
    - It may come after forty
 
    - Phonetic alphabet number
 
    - San Francisco gridder, briefly
 
    - Certain numeral in NASA-speak
 
    - NASA-speak numeral
 
    - Joe Montana, once
 
    - Frisco squad member
 
    - San Francisco NFLer
 
    - San Francisco ballplayer, briefly
 
    - Number in the NATO phonetic alphabet
 
    - West Coast N.F.L.'er
 
    - Monster Park player, familiarly
 
    - Montana, in the '80s
 
    - Montana was one
 
    - West Coast NFLer
 
    - Monster Park NFLer
 
    - Forty-__ (Gold Rush prospector)
 
    - Number in CB lingo
 
    - Joe Montana was one
 
    - NFL player
 
    - Forty-___ (gold-rush participant)
 
    - S.F. gridder
 
    - San Francisco footballer, for short
 
    - Number, in pilot-speak
 
    - San Fran footballer
 
    - Forty-___ (Gold Rush prospector)
 
    - Candlestick Park player, for short
 
    - S.F. footballer
 
    - Forty-___ (gold seeker)
 
    - Ham's digit
 
    - Gold Rush participant, casually
 
    - Frisco player
 
    - California gridder
 
    - S.F. player
 
    - San Fran NFLer
 
    - San Fran gridder
 
    - Digit in military lingo
 
    - Montana, from 1979 to 1992
 
    - What Montana was in the '80s
 
    - San Francisco player, for short
 
    - Aviator's number
 
    - Forty-___ (California Gold Rush participant)
 
    - San Francisco gridder, familiarly
 
    - Super Bowl XLVII player
 
    - San Francisco footballer, in brief
 
    - Montana in the '80s, e.g.
 
    - San Francisco gridder
 
    - Bay Area gridder
 
    - Frisco pro
 
    - Number used by pilots
 
    - Levi's Stadium athlete, informally
 
    - Former Candlestick Park NFLer
 
    - San Fran pro
 
    - Levi's Stadium player, familiarly
 
    - Bay Area pro
 
    - SF athlete, to a fan
 
    - Eight plus one, to aviators
 
    - West Coast pro
 
    - Number spoken by pilots
 
    - Forty follower
 
    - Jerry Rice, e.g., informally
 
    - NFLer of San Fran
 
    - NFL nickname
 
    - Golden State gridder, for short
 
    - Pilot's digit
 
    - Forty-___ (old prospector)
 
    - Bay Area NFLer
 
    - Cali gridder
 
    - Bay Area athlete, for short
 
    - San Francisco athlete, for short
 
    - Montana, in the 1980s
 
    - San Francisco NFLer, informally
 
    - Montana, e.g., informally
 
    - Colin Kaepernick was one, familiarly
 
    - Bay Area NFL player, for short
 
    - SF player, for short
 
    - Levi's Stadium player
 
    - San Fran athlete
 
    - NFLer supported by Sourdough Sam
 
    - SF NFLer
 
    - Bay Area football player
 
    - Brock Purdy, for one