Moon runes is an internet slang to label texts, speeches or other scripts that are seemingly incomprehensible to the audience.
It can also refer to Far-East Asian languages such as Chinese or Japanese. Moon runes can refer either to the language itself or its characters.
Similarly to that, moonspeak is a connecting term for confusing foreign languages.
The term is possible to have originated from J. R. R. Tolkien’s novel The Hobbit, a book that features the expression moon-letters as a mythical element within the plotline.
Another theory for the term’s origin is that it has derived from the term moonspeak, a fictional language that is featured in the 1999 anime Turn A Gundam
The term is not common on the internet, only a handful of sites have featured the expression throughout the years.
In 2008, an article about moonrunes was submitted to the site Urban Dictionary by the account Wael, which has received 493 upvotes to date.