Usually caused by a sudden shock or surprise!
Similar to a "coronary" except you shit yourself.
Some physical preconditions usually are present...
You
ate a
big meal earlier,
You are drinking or stoned and a little
sleepy
You are not expecting a surprise.
Ex:
Bob:
Jesus, I just heard Steve had a colonary last
night!
Dave : Yeah, but he is now resting comfortably and receiving visitors...