<abbr> Manchester United Fan In Name Only. A person who claims to be a die-hard supporter of English Premier League club Manchester United, when in fact he has no clue about the game.
Manchester United's string of successes mean it has legions of fair-weather fans who would dump the club at the first sign of trouble. They're MUFINO!
Manchester United Fan In Name Only. An acronym coined by Sanish Fernandez (word surgeon in Bangalore, working for a rather large IT firm)
"That Joe, he's a MUFINO: when the Mancs win 1-0, he comes out screaming, thumping his chest, but as soon as one of the London teams start to lead, he declares them champions-elect."