nominative singular masculine past participle (nisinna), contracted with enclitic -ṁ (nisinnaṁ)
Analysis. ni- (down, into) + √sad (sit) + -inna (past participle); nisinna denotes the state of having seated oneself downward.
Etymology. √sad is cognate with English sit, German sitzen, Latin sedēre (sedentary). The prefix ni- (down, into) carries its spatial sense of descent and settling: to sit is to descend into a seated position.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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