8.4.7
अह्नोऽदन्तात्
Operational rule vidhi
The ण is the substitute of न of अहन् , when it is preceded by a word ending in अ , having in it a letter capable of producing a change.
Word by word (padaccheda)
Substitute / term अह्नः prathamā · ekavacanaSubstitute / term अदन्तात् prathamā · ekavacana
- Substitute / term Prathamā (1st case): in operational rules, the substitute or the thing introduced; in definitions, the term or its referent.
Full reading
अह्नः अदन्तात्
Pāṇini leaves out words that carry over from earlier sūtras. Expand to see the rule as a reader actually understands it.
Commentary
The ण is the substitute of न of अहन् , when it is preceded by a word ending in अ , having in it a letter capable of producing a change.
Thus पूर्वाह्णः "fore-noon"; अपराह्णः "after-noon".
Why do we say "ending in अ"? Observe, निरह्नः, दुरह्नः ॥
The word अह्न is substituted for अहन् by 5.4.88. The word अह्न being used in the sutra as ending in अ, the rule does not apply to other words. Thus दीर्घाह्नी शरत् ॥ The word अह्नः in the sutra is in the nominative case, and should not be construed as the genitive of अहन्, because all sthanins are exhibited in Nominatives as, वनं 8.4.4, वाहनं 8.4.8, यानं &c. The compounding takes place by 2.2.1, then is added the samasanta affix टच् 5.4.91, and अह्न substitution by 5.4.88. The word दीर्घाह्नी is a Bahuvrihi compound and not a Tatpurusha, and hence the affix टच् does not apply to it. The feminine ङीप् is added by 4.1.28, there is elision of अ of अहन् by 6.4.134.
Śrīśa Chandra Vasu, The Ashtadhyayi of Panini (1897), via ashtadhyayi.com.