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1 definition by G P

 
1.
The one week out of the year when a man has a cold, and doesn't feel good, and excercises his right to complain and whine- contrary to every fucking day of a woman's life when we have to hear you complain.

The man flu is usually accompanied by a lack of sympathy from females, which further advances the adverse symptoms of the man flu.
GF: Ugh, BF is so annoying and whiny, all he has is a cold.
BFF: Oh, yeah, the Man Flu.
BF: GOD FORBID you take care of ME for ONE DAY and not complain.
by G P January 03, 2008