tesamayaṁ

tesaṁ mayaṁ

genitive plural pronoun + instrumental singular pronoun (contraction in sandhi)

of them by me
by me concerning them

Analysis. tesaṁ (genitive plural of ta, 'that/those') + mayaṁ (instrumental singular of ahaṁ, 'I'), contracted in sandhi: tesamayaṁ. The phrase typically appears in narrative passages meaning 'at that time, then' or in a temporal/circumstantial sense.

Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.

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