masc instr sg of acapala (adj); nt instr sg of acapala (adj)
Analysis. a- (not) + capala (shaking, trembling): literally 'not shaking', hence unshakeable, steady in bearing or mind.
Etymology. The prefix a- (without, not) negates capala, which is related to Sanskrit capala 'trembling, unsteady' and ultimately to the root meaning 'to shake or tremble' (cf. Latin cavillor 'to quibble', though less directly); the double negation creates a positive quality of stability and constancy.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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