3rd person plural optative (conditional) of upasaṅkamati; tenupasaṅkameyyuṁ is a contraction of te + upasaṅkameyyuṁ (te = they, nom. pl. masc.).
Analysis. te (they) + upa (up close to, near) + saṅ (together, with) + kamati (goes); literally 'they might go together up close to'—a formal approach or respectful drawing near in a doctrinal or social context.
Etymology. upa- (approach, from proximity root) + saṁ- (togetherness, from PIE *sem- cf. English 'same') + √kam (move, go, cognate with English 'come'). The optative mood signals propriety or possibility.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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