pronoun (nominative/accusative neuter singular sandhi form)
Analysis. tad (neuter singular of ta 'that') + eva (emphatic particle 'itself, just'), with sandhi: final -d of tad remains before initial vowel e- of eva.
Etymology. ta descends from Indo-European *to- (demonstrative 'that'); cognates: English 'that', German 'das', Latin 'istud'. The particle eva (from √i 'go') intensifies by pointing: 'it goes to that very place', hence 'that itself'. Together tadeva marks identity and exclusivity: 'not something else, but that itself'.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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