Paganism (from Latin paganus, meaning “country dweller, rustic”) is a term which, from a Western perspective, has come to connote a broad set of spiritual or cultic practices or beliefs of any folk religion, and of historical and contemporary polytheistic religions in particular.

The term can be defined broadly, to encompass the faith traditions outside the Abrahamic monotheistic group of Judaism, Christianity, and Islam. The group so defined includes the Indian religions (such as Hinduism, Jainism), Native American religions and mythologies and Shinto as well as non-Abrahamic ethnic religions in general. More narrow definitions will not include any of the world religions and restrict the term to local or rural currents not organized as civil religions. Characteristic of pagan traditions is the absence of proselytism and the presence of a living mythology which explains religious practice.[1]

The term “pagan” is a Christian adaptation of the “gentile” of Judaism, and as such has an inherent Christian or Abrahamic bias, and pejorative connotations among Westerners,[2] comparable to heathen, and infidel, mushrik and kafir (كافر) in Islam. For this reason, ethnologists avoid the term “paganism,” with its uncertain and varied meanings, in referring to traditional or historic faiths, preferring more precise categories such as polytheism, shamanism, pantheism, or animism.

Since the later 20th century, “pagan” or “paganism” has become widely used as a self-designation by adherents of neo-paganism.[3]

Wikipedia bitches. TFD defines it as any non Christian, Jew, or Muslim. And that tends to be the definition people tend to use.