sandhi form: 3rd person singular present passive of vuccati + vocative āvuso
Analysis. vuccati (is called, is said) + āvuso (friend, vocative plural āvuso). The contraction occurs at a pause: final -i of vuccati elides before the initial ā of āvuso, and the two words merge into a single phonetic unit in recitation.
Etymology. vuccati from √vac (speak, say) — cognate with Latin vox (voice), English voice; āvuso from ava- (down, off) + sus- (to urge, drive forward), literally "driven forward", hence a companion or friend. The prefix ava- here gives the sense of directedness and attention toward another.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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