look up any word, like dirty sanchez:
 
1.
WHEN SOMETHING GOES TERRIBLY TERRIBLY WRONG, OR BREAKS. USUALLY RUINS YOUR ENTIRE DAY AND MAY CAUSE SOME PEOPLE TO UNCONTROLLABLY SHIT THEIR PANTS.
TOM: WHERES YOUR BIKE?

ISHKEBIBEL: THE FUKIN THING SHAT THE BED LAST NIGHT, CAUSING ME TO DEFECATE IN MY PANTALOONS.
by WONDERBREAD AKA WHITE CHOCOLAT August 01, 2008
 
2.
To got up really early in the morning much earlier than you ususally would.
Man I Shat the bed today. I had to get up at 6am to catch the plane.
by Jaber the hut October 23, 2013
 
3.
a slang phrase that is often used to mean 'woke up early', the reasoning being that if you shat the bed you would get out of it asap.
-'shat the bed'?
-'nah couldnt sleep'
by Lucys_Drowning September 01, 2008