'Glotnot' is a word created entirely by its user, and has no true meaning. It is most commonly used only by its creator, and under no known circumstance has it occured that someone else has used it for a title or username.
In other words, this name means absolutely nothing, except maybe to say that if you are a 'Glotnot', then you are 'not a glot' (though the word 'glot' has no meaning either).
The closest word to 'Glotnot' or 'glot' is 'glottal', which is a term used for a glottal stop. However, there are no glottal stops in 'Glotnot' or 'glot', and the glottal stop was unknown to 'Glotnot' before the username was created.
This name is used by its creator on a variety of sites and forums, including Neoseeker and Wikipedia.
Trivia
Glotnot is a member of the Grey Dog Software Forums. He is an avid player of the game Mafia.