masculine accusative singular
Analysis. upā + √sak (upāsaka: upa-√as + -ka). upa- 'close beside' + √as 'sit' → 'one who sits near', i.e. attends on; -ka is a diminutive or agent suffix.
Etymology. From upa- 'up close to, near' + √as 'sit' (cognate with Latin assidēre 'sit by, attend'). The concrete image of sitting close beside the teacher crystallized into 'devoted follower' in Buddhist usage.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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