Well, this is one word that would never be used to describe me as I am certainly not mysterious.
However, few people really know me, so maybe I can claim 50% .
I wonder if you would count our phone number as arcane? It’s only known to three people, so regardless of not having voice recognition on our cheap handset (less than £10) or paying extra for a service we don’t require, I have a pretty sure bet of who’s ringing me!
Written for Fandango’s One Word Challenge