indeclinable (accusative singular neuter form); or adverbial locative
Analysis. eka (one) + manta (side, direction); from the root √man meaning 'to think' or 'to measure', here meaning a measured portion or side of space.
Etymology. eka 'one' (from PIE *oi-ko-, related to English 'one' and Latin 'unus') compounds with manta, which derives from √man 'measure, think'. The phrase originally meant 'to the one side' or 'along one measured direction', used of physical separation and then of deliberate withdrawal into privacy for conversation or reflection.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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