Heretic

The plural of Heretic is Heretics.

A Heretic seems to be anyone who does not agree with a specific Religion.

Therefore probably everyone on the Planet can be considered to be a Heretic to some Religion.

An example. About 1/6 of the population of the Earth belongs to the Catholic Church.  Since the Catholic Religion is practiced by only about 1/6 of the world's population the other 5/6 of the world must be Heretics, at least to the Catholics.  The Muslims seem to consider all those who are not Muslim to be Heretics, infidels, or Pagans, and since this includes the 1/6 of the world that is Catholic, everyone in the world is a Veretic to some Religion.

At least one Religion, Wicca, does not consider those who are not of the same belief as they are, to be Heretics.  

The idea seems to be "You will believe in my God as I 'know' him or you are a Heretic," or worse. More likely the Religion will want to kill you for not calling God by the same name as they refer to Him by.

This concept has really helped people to just get along!!!