Commissioner Roger Goodell notified Adams of the fine Monday, and league spokesman Greg Aiello said it is for conduct detrimental to the NFL. Adams was seen making the gesture while in his luxury suite and again on the field after Sunday's 41-17 victory.
The 86-year-old Adams issued an apology a couple of hours later, saying he got caught up in the excitement of the moment.
Goodell was at the game, after having breakfast with Adams. The league said that Goodell left Adams' suite at the end of the third quarter and spent the fourth quarter sitting with fans in the end zone before leaving the stadium.
The Titans declined to comment after the fine was issued. But Adams said in his earlier statement that he expected league discipline for his actions and would accept any punishment.
"I do realize that those types of things shouldn't happen," Adams said in that statement. "I need to specifically apologize to the Bills, their fans, our fans and the NFL. I obviously have a great deal of respect for Ralph Wilson and the history we have shared."
The NFL fined former 49ers owner Eddie DeBartolo $1 million after he pleaded guilty to a felony and suspended him for the 1999 season.
Since then, the biggest fine handed down by the NFL to an individual was $500,000 to New England coach Bill Belichick for the Spygate scandal. The league also fined the New York Jets and former coach Eric Mangini $125,000 in September for violating its rules on injury reporting with Brett Favre last season.
Adams and Wilson were original owners in the American Football League, and Sunday's matchup was a legacy game with both teams wearing throwback uniforms. Wilson was inducted into the Pro Football Hall of Fame this year, and the two franchises have been involved in some emotional playoff games.
The Bills staged the greatest comeback in NFL history on Jan. 3, 1993, against what was then the Houston Oilers in a 41-38 overtime victory, while the Titans pulled off the Music City Miracle in the 1999 playoffs, a game-winning kickoff return for a touchdown with 3 seconds remaining.
"They're close. There's been some tremendous matchups over the years between the two clubs. The playoff loss there, the Music City Miracle here ... There's a great deal of history here. I know this was a game he'd been looking forward to," Fisher said.
This isn't the first time Goodell has punished someone with the Titans. He handed down a five-game suspension to defensive tackle Albert Haynesworth in October 2006 for swiping his foot across the head of Dallas center Andre Gurode.
Players have been fined for the NFL for making this same gesture that Adams made. San Francisco kicker Joe Nedney was fined $7,500 in October 2007, and Michael Vick was fined $10,000 and donated $10,000 to charity in 2006 while playing in Atlanta.
"The league holds us as players to a higher standard, so to have an owner flip the bird not once but twice the league has to hold him to the same standard if not more," Bills safety George Wilson said Monday before news of the fine. "He's at the top of the hierarchy. If you don't hold him accountable, then you're questioning the integrity of the system."
Buffalo defensive tackle Marcus Stroud saw footage of Adams on TV but didn't care.
"He owns that team and Mr. Wilson owns our team. That's about the gist of it, as far as it goes with me. It's not like he can come down and strap up and put on any pads or anything like that. It doesn't bother me. If that's what he wants to do, go for it," Stroud said.
Copyright 2009 by The Associated Press