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To vomit and have diarrhea at the same time.

The entomology comes from the act of splitting, i.e. one thing being diverted or cut into two different directions or entities and the chewy, i.e. that which has been eaten or chewed.
After eating that old potato salad, I spent the night rotating from face up to face down at the toilet, That crap made me split the chewy
by gweschuck76 January 19, 2011