A second name, one that is commonly concidered as a Nickname.
He wrote down his Pseudonym, instead of his actual name.
The nickname that you use to call your animal/pet after an event occurs such as a sex scandal or something of that nature to the person that they're named after.
Ex: A bird named Bill Cosby. Would then be referred to as BC,Coby,Bill,etc.
Guy: where's Bill Cosby?
Can of peaches: I believe you mean Beeyacobbee. It's his scandal pseudonym.