Some Terminology

I hope someone can define the following terms for me:

"rat engine"??
"mouse motor"??

I've looked everywhere for their meaning, but so far I have been unsuccessful. :banghead: Any help would be appreciated.

Rat = Big Block
Mouse = Small Block.

Pertains to Chevrolet V8 engines - the 'Rat' is a Mark IV Big Block (396, 402, 427, 454) and the 'Mouse' is the venerable original Small Block.
:)

Solves that!!

Thanks guys. Like I said, I've had trouble finding the definition of these terms.