The NFL ain't buying it, or just didn't care for Jerry Jones' explanation over why he flipped fans the middle finger in the closing moments of Sunday's Cowboys game ... 'cause the league just hit the longtime owner with a massive $250K fine!
While the NFL hasn't released a statement announcing the fine, several NFL insiders reported the 6-figure bill on Tuesday ... about 48 hours after the incident.
82-year-old Jones admitted to the one-finger salute, but said it was all a big accident ... explaining he meant to give a harmless thumbs up to the many Big D fans at MetLife Stadium.