accusative singular neuter, or adverbial form; from satta 'seven' + aha 'day'
Analysis. satta (seven) + aha (day) in accusative/adverbial construction, typically in locative phrases like sattāhaṁ (for seven days)
Etymology. satta from Indo-European *septṃ (cognates: Latin septem, Greek hepta, English seven); aha from Indo-European *aǵh- (day, related to Sanskrit aha and cognate to Greek achós 'grief, distress' as a day's duration)
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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