Who is an authority on what can be called a “Bible”?

Question

(I'm not entirely sure whether this question is in scope of this SE, but this appears to be the SE closest to the issue)

In Poland, there is a region called Silesia, which is inhabited by people speaking a distinct dialect, which can be quite different from the Polish language at times. One of the Silesians decided to write a book about interpretation of chosen Biblical tales (mainly from the New Testament) inspired by his grandmother's tales. The book is called "Biblia Ślązoka" (which can be translated to "Silesian's Bible," although the English Wiki does not have an article on it). This adaptation is aimed mainly to show similarities between Biblical events and history of Silesia and is written in the distinct dialect. I've heard about criticism for calling this book a "Bible," because it isn't a translation of the Biblical texts from their original language but rather from the Millennium Bible.

In light of all this, who is an authority of what should and what should not be called a "Bible," and what can they do in the matter? As the texts themselves are in public domain, from a legal standpoint anyone can make any derived works from it without any repercussions, or perhaps even title a totally unrelated work as "Bible."

Answer 1

There really isn't a body that controls what is called a Bible and what isn't. There are groups that put their stamp of approval on translations and study Bibles though. For instance, the Assemblies of God funded the study notes for the Life in the Spirit Study Bible which has notes and essays (set aside from the text and marked as additions) specifically for Pentecostal and Charismatic believers

Being translated from the Millennium Bible would make the Polish translation you ask about what is called in theology a "daughter translation." Nothing wrong with these at all as long as the reader is aware of it. I have used a few of them for study, such as the Septuagint in English (LXE) and Vulgate in Modern English. The Douay–Rheims is an excellent example of a daughter translation as it is in English (around the time of the King James) but translated from the Vulgate (The D-R has also been updated several times over the centuries).

Most books in the church realm that have Bible in their title will be one or both of the Testaments, a New Testament with Psalms and Proverbs, etc. If it were a translation of a single book or a set of books, it would be listed as "A Translation of Mark," or "The Gospels in Today's Language." A book that is mostly selected tales would be classified here in the United States as "Bible Stories" or "Selected Bible Texts."

Answer 2

The word "Bible" is derived from the Greek word "biblio", meaning "book". In that sense, just about any book can be called a bible.

But because Christians believe the Bible is the authoritative source for doctrine, the word "Bible" has taken a connotation meaning "authoritative". So sometimes books will include the word "Bible" in their title to imply that they are the authoritative source on their topic.

We see this a lot in the tech industry, for example, the JavaScript Bible or the Linux Bible. If those books can use the word "Bible", the "Biblia Ślązoka" should be able to as well. Any informed reader should be able to tell by opening and looking through it that it is not a translation of either the Jewish or the Christian Bible.