masc nom pl of mudha (pp); fem nom sg of mudha (pp); fem nom pl of mudha (pp); nt nom pl of mudha (pp); …
Analysis. mudhā is the instrumental singular (or locative) of mudha (past participle), reanalyzed as an adverbial particle. The sense 'for nothing' arises from the instrumental meaning 'by means of foolishness' or 'in a foolish manner', hence 'to no purpose, uselessly'.
Etymology. mudha is a past participle from √mudh- (to be confused, bewildered). The root √mudh- is cognate with Sanskrit muddha- and likely related to English 'muddle', both sharing the sense of confusion and disorder. The adverbial instrumental form froze into a preposition-like particle expressing purposelessness.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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