And here's yet another four-lowercase-letter-name for you, then. Dunno about the other two, but I've been using this handle for over twenty years, it was originally the auto-generated username I got assigned on one of my university's servers (generated from my initials).

Low character count handles are a scarce resource, and are often highly-sought after (people were paying crazy amounts for some names on twitter in its heyday). Almost any 2-, 3-, or 4-character sequence is going to be either a word or an abbreviation of something that's meaningful to someone out there.