indeclinable (vocative particle)
Analysis. ā + vuso, where vuso is a nominalized form of the root meaning 'to turn' or 'to call'; literally 'one called toward', hence an address to someone summoned or approached with respect.
Etymology. ā (toward the speaker) + root √vac/√vas (to call, speak, dwell); the prefix ā reverses the direction, making the compound vocative in force—'toward-you'. The form appears in Sanskrit as āvus, avus (a revered elder or ancestor), and reflects the same Indo-European root as Latin vocāre (to call) and English voice.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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