Anyone who disobeys Abrahamic "ten" commandments 0, 1 and/or 2 (depending how you count them) – that is, anyone who does not worship the Abrahamic God as the first and foremost deity.
I'm not sure whether atheists count as pagans. (Buddhists probably are…? But really, the term was designed for the religious practices of southern and (north-)western Europe that the early-ish Christian church wanted to wipe out.)
