Earlier quoted context omitted.
* is the wildcard in some forms of regular expressions, such as file name globs.
A glob isn't a regular expression, and indeed one of the reasons it isn't is that it lacks the Kleene star - which is the thing an asterisk does in the typical regular expression syntax.
Star-free languages are regular languages without the Kleene star.
https://en.wikipedia.org/wiki/Star-free_language
But I'm not an expert in formal languages and maybe you are.