I am trying to learn more on the art of meatcutting and have looked at many a picture of beef sides and where restaurant steaks come from.
My assumption is that what we call backstrap, that oh so tender piece of meat outside of the rib cage and lining both sides of the vertebrae stretching from near the butt to the shoulder, is what restaurants call loin meat.

I am wondering what they call the even more tender muscle inside the rib cage that we call the tenderloin?

I am using the below page for reference:
http://consumer.certifiedangusbeef.com/cuts/beef_cuts_poster_4047.pdf
It doesn't show what I call the tenderloin, only what I call backstrap that they call loin.
Thanks and happy Sunday

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