It's the effect greasy, nasty fast food has on you about 15 minutes after you eat it: You feel lethargic, tired, not wanting to do anything but veg on the couch.
Well this sucks. I just got a McHangover from that Big Mac super sized meal.
by asswip'e December 18, 2007
The overall bad feeling you get after consuming a large amount of McDonalds food.
Oh my GOD! I got a huge McHangover, I feel like Im dying!!
by Obamazing December 30, 2009
Its the horrible feeling you get when you eat a crap load of mcdonalds at night and feel disgusting and sick the next morning.
I ate 20 mcnuggets and 2 medium frys last night, this mchangover is gonna make me throw up
by MonoplyHater October 16, 2010