genitive plural
Etymology. From Indo-European *kewes- 'to notice, perceive' (cognate with Sanskrit kuśala, Greek κοῦος 'keen-sighted'); originally 'able to perceive clearly,' hence 'skilled' and 'wise.' In Buddhist doctrine, kusala denotes actions rooted in non-greed, non-hatred, and non-delusion (akusala-mūla).
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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