“Metadata” is a much-used by seldom fully understood term. The word “meta” itself is an overused term loosely meant to communicate “separate from” or “abstraction of” the subject but this is a trivialization of something far more complex. The WikiPedia article about the word “Meta” starts like this:
Meta (from the Greek preposition and prefix meta- meaning “after” or “beyond”) is a prefix used in English to indicate a concept which is an abstraction from another concept, used to complete or add to the latter.
I highly recommend reading up on “meta” to get a better understanding of the term and the image above.