Do you have the right to be an atheist?

[ErGingerbreadMandude]

I didn't change the definition of a God i simplified it.

Read my post and understand it.

Well if you do have unicorns inside your fridge you are inclined to prove that to us(Burden of proof).

Well if you create a definition of a unicorn as "anything which has a somewhat pointy piece or edge" then yes,you'd have a unicorn inside your fridge 
according to your definition .
If you can convince a quite huge group of the human population that " anything which has a somewhat pointy piece or edge " is a unicorn.Then i'd 
be inclined to accept your definition and consider " anything which has a somewhat pointy piece or edge " as a unicorn.I will accept it.Of course 
the trick is to convince this huge mass.Good luck.

In my condition,i didn't "create" a definition for "God".I simply followed an already accepted definition of "God" which was already accepted by a significant mass.
Also i provided enough input to justify my action which was to choose this particular definition.You'd have to do that too.