past participle (accusative singular masculine + iti quotative particle)
Analysis. araññabhūtaṃ + iti: araññabhūta 'forest-become' (past participle of araññabhavati) + iti quotative particle 'thus, so'. The -ṃ is accusative singular agreement with a noun or participle functioning as the object of the quotative frame.
Etymology. araññabhūta compounds araññā 'wilderness, forest' (from araṇa- 'desolate', of uncertain origin) + bhūta, past participle of bhavati 'becomes, is' (cognate with English 'be', Latin futurus, Sanskrit bhavati, from Indo-European *bheuH- 'grow, become'). The imagery is literal: something that has transformed into forest or taken on the quality of wilderness.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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