The deep regret you feel within your bowels after having engorged yourself on a late night McDonalds combo meal.
I definitely should not have eaten that Big Mac just now. I got a case of the McGrets.
by splixx December 26, 2009
The feeling you have a couple of hours after eating a greasy fast-food meal.
Rogan had mid-afternoon McGret after consuming two cheeseburgers and fries for lunch.
by hillsburgh_hillbilly June 18, 2009
The feeling you get after eating McDonalds.
I McGrets having that quarter pounder with cheese. I feel like i'm going to throw up.
by altruisticaussie March 10, 2009
The regret you feel when you realize you want something other than the thing you actual order, typically felt while driving away from the fast food place.
"Dude I felt so much McGret last night I knew I should have gotten a Big Mac and not the McChicken"
by Ramdomchick268 February 25, 2015