past participle (nominative singular neuter) of tuṇhībhavati (causative passive or middle voice of bhavati 'to become', with tuṇhī 'silent')
Analysis. tuṇhī (silent, tacit) + bhūta (became, past participle of bhavati 'to become'); the phrase means 'having become silent' or 'having fallen into silence', often used in the canon of the Buddha or arahat remaining silent rather than responding to a question.
Etymology. tuṇhī is from √tuṇh- (to be silent, to hush); bhūta is from √bhū (to become, to be), cognate with English 'be' and Latin 'fuit'. The root √bhū appears in Sanskrit bhavati and is part of the Indo-European family *bʰeuH- (to grow, become, be).
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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