तीररूप्योत्तरपदादञ्ञौ

Operational rule vidhi

The affix अञ् comes after a word ending with तीर and the ञ् comes after a word ending with कप्य , in the remaining senses.

Word by word (padaccheda)

Left context तीर- रूप्य- उत्तरपदात् pañcamī · ekavacanaSubstitute / term अ - ञौ prathamā · dvivacana

Left context Pañcamī (5th case): "after X", the operation applies to what follows (1.1.67 तस्मादित्युत्तरस्य). Also used for limits and sources.
Substitute / term Prathamā (1st case): in operational rules, the substitute or the thing introduced; in definitions, the term or its referent.

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Pink letters are it-markers (anubandhas), tags dropped by 1.3.9. Hover or tap one for the rule that marks it, or try the it-letter finder.

Full reading

तीर-रूप्य-उत्तरपदात् अञ्-ञौ

Pāṇini leaves out words that carry over from earlier sūtras. Expand to see the rule as a reader actually understands it.

Commentary

The affix अञ् comes after a word ending with तीर and the ञ् comes after a word ending with कप्य , in the remaining senses.
This debars अण् ॥Thus काकतीरम्, पाल्वलतीरम्, वार्करूप्यम्, शैवरूप्यम् ॥ The words formed by अञ्, take the affix ङीप् in the feminine 4.1.15; those in ञ take the affix टाप् 4.1.4. The sutra is not enunciated as तीररूप्यान्तात्, for had it been so, the affix would apply to बहुरूप्य also, where रूप्य is final, but cannot be called uttara-pada, as 'bahu' is not a pada but is an affix 5.3.68. Therefore, we have बाहुरूप्यम् formed by अण् ॥

Śrīśa Chandra Vasu, The Ashtadhyayi of Panini (1897), via ashtadhyayi.com.