How Override naming conventions for mongodb document

Model for MongoDb looks like follows

class User
  include MongoMapper::Document
  key :name, String
end

Name of the table in MonoDb is users.

How to override naming convention for MongoMapper::Document ?

Why do you want to rename it in the first place? Name convention is
there for a reason - I think
you're on a slippery slope there.
You can rename your class, obviously.