The definition that I have found works best for Paganism comes from Isaac Bonewits
To most of us, Paganism is a general term for polytheistic religions old and new...
Some would add pantheistic
to that, which I will grant. Pagan
appears to come from the
paganus, meaning country dweller/hick. Interestingly, some claim that it was originally used
by the Roman
army to mean civilian
This definition will envelop just about all of the non-monotheistic faiths, with exceptions raised
for certain sects of Taoism and Buddhism. So that means that Zoroastrianism, Judaism, Christianity,
and Islam are not 'Pagan' (though some of them have happily used this word to refer to others),
while Hinduism is in right alongside Wicca and the Church of All Worlds.
Under this definition, a given Pagan might or might not:
Some like to further divide the term into Neopaganism, Mesopaganism, and Paleopaganism, based
on time, liberalism, or some combination.