Fair enough. English isn't my first language, so I basically go with what the dictionary says, in this case "An adherent of a polytheistic religion in antiquity". :)

Pagan is merely derived from the Latin word for “rural” or “rustic” because Christianity took hold in Roman cities first and non-Christian Roman gentry held out in the countryside.

Mostly, but I don’t think a Christian would call a Muslim or a Jew ‘Pagan’. It’s more of a synonym for polytheism.