What's wrong with adding "just syntax" for now?
"Just syntax" is the difference between how you use the regex engine in Perl, and how you use it most other languages (where load a library, compile a pattern, and match it).
"Just syntax" is often the difference between a feature that's used very often, and one that's mostly avoided.
"Just syntax" is also what distinguishes Perl from most other languages, and Perl 6 from Lisp. (Ok, my last point about Perl 6 is not 100% serious, but you get the picture).