indeclinable + enclitic (sandhi form aññatreva)
Analysis. aññatra (elsewhere, apart) + eva (just, only) = without, completely separate; emphatic form stressing total exclusion.
Etymology. aññatra from aña (other) + -tra (locative suffix, place where). Aña is cognate with Sanskrit anya, from Indo-European *an- (one, single), the source of Latin alius (other) and English 'alien'. The suffix -tra creates a place-word: 'the place of otherness.' Eva is an emphatic particle (just, verily), unrelated to Indo-European but used to sharpen the exclusionary force.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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