It's actually spelled cecum and all mammals have one, not just rats. It is at the end of the ileum, which is connected to the jejunum, which is connected to the duodenum. The cecum is a small pouch where the small intestine and large intestine meet. Those 4 parts make up the small intestine.
The cecum looks like a small thumb connected to the small intestine.
by Jonnathin August 27, 2005
1 more definition
A little sack in the inside of a rat that holds it's bodily waste.
Alex, don't pierce the secum or the whole room will smell like shit.
by DavieK July 30, 2005