2. Belonging to, characteristic of, or constituting another and very different place, society, or person; strange. See Synonyms at foreign. 3. Dissimilar, inconsistent, or opposed, as in nature: emotions alien to her temperament.
n, pl -thens or -then. 1. (Alternative Belief Systems) a person who does not acknowledge the God of Christianity, Judaism, or Islam; pagan. 2. an uncivilized or barbaric person. 3. (Alternative Belief Systems) the heathen (functioning as plural) heathens collectively.
Heathen is an old word in Northern European languages such as English. Its original meaning was probably dweller-on-the-heath, similar to the original country-dweller meaning of the Southern European word  pagan .