runic

/ˈrunɪk/

Runic writing consists of ancient characters that are tough to decipher. These days the word might better fit a doctor's signature or a confusing instruction manual.

Runes were the symbols used by Germanic people for writing in the Middle Ages. In those days, writing was rare, and people tended to look at it is as magical and a little threatening. Runic inscriptions continue to have an air of mystery about them, because they're so hard to read.

Definitions of runic

1. adjective

   relating to or consisting of characters from an ancient alphabet
   “runic inscription”