Is a slang expression Zero at the Bone?

The phrase "Zero at the Bone" is not a common slang expression. It's likely a made-up phrase or a very specific idiom used in a particular context.

If you can provide more context, I might be able to help you understand its meaning. For example:

* Where did you hear it? Was it in a book, movie, or conversation?

* Who said it? Was it someone you know well, or someone you just met?

* What was the context? What was the speaker talking about?

Without more information, it's difficult to say what "Zero at the Bone" means.