pronoun + particle; sandhi form of taṃ + hi
Analysis. taṃ (accusative singular of ta 'that') + hi (emphatic particle 'truly, indeed'); the final -ṃ of taṃ elides before the initial h- of hi, yielding tañhi. The particle hi reinforces the pronoun with emphatic force, common in narrative and doctrinal contexts to assert that a thing or teaching is genuinely what it is.
Etymology. ta descends from Indo-European *to- (compare English 'that', German 'das', Latin 'iste'). The particle hi is an old enclitic emphasizer, akin to Sanskrit ha and Greek -ge, reinforcing what precedes it with the sense 'truly, verily'.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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