indeclinable
Analysis. para- (other) + hetu (reason, cause) — literally 'another's reason', used adverbially to mean 'for another's sake or benefit'.
Etymology. para from Sanskrit para-, Indo-European *per- 'forward, through' (English 'far', 'further'); hetu from √hṛ 'seize, take' (Sanskrit hetu, English 'her-' in 'hereafter'), the root sense 'that which is seized upon' becoming 'reason, cause'.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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