pagan vs heathen

pagan and heathen both are nouns.

Word	Noun	Adjective	Verb	Adverb
pagan	Yes	Yes	No	No
heathen	Yes	Yes	No	No

As adjectives, pagan and heathen are synonyms defined as:

pagan and heathen: not acknowledging the God of Christianity and Judaism and Islam

Other synonyms of pagan include ethnic, heathenish.

As nouns, pagan and heathen are synonyms defined as:

Other synonyms of pagan include gentile, infidel.

pagan (noun)	heathen (noun)
a person who does not acknowledge your god	a person who does not acknowledge your god
a person who follows a polytheistic or pre-Christian religion (not a Christian or Muslim or Jew)
someone motivated by desires for sensual pleasures

pagan (adjective)	heathen (adjective)
not acknowledging the God of Christianity and Judaism and Islam	not acknowledging the God of Christianity and Judaism and Islam