English
allotheism
From allo- + theism.
Proto-Indo-European *h₂el- ‘beyond, other’
Proto-Indo-European *h₂élyos ‘other, another’
Proto-Hellenic *áľľos
Ancient Greek ἄλλος ‘other’
English allo-
Proto-Indo-European *dʰeh₁- ‘to do’
Proto-Indo-European *dʰéh₁s ‘god, godhead, deity’
Proto-Indo-European *dʰh₁sós
Proto-Hellenic *tʰehós ‘god, deity’
Ancient Greek θεός ‘god’
English theism
Today it means
noun Worship of a god or gods that are foreign to one's own land.
Language periods are conventional ranges, not dates for this word.
Etymograph / allotheism