Coach Thomas Tuchel admitted on Sunday that it would be "very difficult" for Cavani to be fit for Tuesday's first leg at Old Trafford.
The French champions have since assessed the 31-year-old and ruled that he will not be fit to make the trip to Manchester.
"The examinations carried out revealed a lesion of a tendon on the right hip," a
The absence of Cavani, who has 21 goals from 25 games in all competitions this season, comes as a big blow for the runaway Ligue 1 leaders. Tuchel's team are already without Brazilian attacker Neymar, who has been out since January with a broken metatarsal, while Marco Verratti is also a doubt.
Cavani was replaced by Kylian Mbappe in the Bordeaux match and will return to his place in the starting XI in the Champions League.
With two members of their star trio missing, Tuchel is worried they must change their strategy for the meeting with Ole Gunnar Solskjaer's team.
"Without [Neymar], maybe without Marco, maybe without [Cavani], now we need a plan D," he told
"I can't think about so many different plans in advance. We have to analyse Manchester United, we have to stay calm and confident.
"Normally, my opinion is definitely clear: for a game against Manchester United, for a game against Liverpool or even against Red Star Belgrade, you need your key players with confidence, experience, quality, who are used to playing that kind of game, are used to playing big games full of pressure, who are used to managing the pressure."
Meunier is also set to miss the midweek clash after it was confirmed he suffered a concussion during the game against Bordeaux and will need to be assessed again next week.