A name of a random dude from the Internet. He searched for a very special name, he can use in a game, and he wanted, that no one had this name before.
Who is Lord Laberstein?
A stone is a natural material. It's often grey and hard. The humans in the stoneage used stones to build tools.
But I've got a guestion: Why tf did you searched for "Stone" in the Urban dictionary.
author: haha lol, this dude searched for stone.
Dude: haha lol, this author wrote literally the entry for stone in this dictionary