We have a file that is not very clear when looking at the Z., Do you see this as barred Z or bold Z? This file focuses on mapping isomorphism and homomorphism. Thank you.
As with any typeform, the surrounding text will give you a clue. If there is no context from which to determine an answer to your question, either bold or barred will give the reader the same information. As I research the use of the bold vs. the barred letter Z in mapping notation, I find that either is used. In this case, the typeform itself bears no specific or unique mathematical meaning.