1. The day spent in bed nursing a hangover

2. Following a night of heavy drinking/debauchery you might spend the next day sitting in bed watching day-time TV or re-runs from the comfort of your bedroom

3. Being so hungover or ill that you are unable to physically move your legs and leave the bed
Examples:

1. The day after his 21st Birthday, Chris had a Polio Day and spent his time watching all of Dexter Season 2.

2. The Dickinson College student was so sick after a night of drinking that the entire next day was a Polio Day and he did not move his legs once.
by CC89 July 11, 2011
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