6.1.96
उस्यपदान्तात्
Operational rule vidhi
In the context of संहिता, ऌhen a अवर्ण not occurring at end of a पद is followed by the word 'उस्', both of them are replaced by a single पररूप.
Word by word (padaccheda)
Right context उसि saptamī · ekavacanaLeft context अपदान्तात् pañcamī · ekavacana
- Right context Saptamī (7th case): "when X follows", the operation applies to what precedes (1.1.66 तस्मिन्निति निर्दिष्टे पूर्वस्य). Also a condition or domain ("in the sense of").
- Left context Pañcamī (5th case): "after X", the operation applies to what follows (1.1.67 तस्मादित्युत्तरस्य). Also used for limits and sources.
Dotted words are technical terms, dashed ones pratyāhāras (names for classes of sounds or affixes). Hover or tap one to see its card.
Full reading
उसि अपदान्तात्
Pāṇini leaves out words that carry over from earlier sūtras. Expand to see the rule as a reader actually understands it.
Commentary
For the अ or आ (not standing at the end of a पद or full word) + उ of उस the Tense-affix, the second vowel is the single substitute.
The आत् is understood here. This debars the guna substitution taught in 6.1.87. Thus भिन्द्या + उस् = भिन्द्युः, छिन्द्या + उस् = छिन्द्युः ॥ अदा + उस् = अयुः, (लुङ् of दा) अया + उस् = अयुः ॥ All these are examples of लिङ् (Potential) and लङ् (Imperfect). Thus भिन्द् + यासुट् + झि (the यासुट् is added by 3.4.103) = भिन्द् + य + उस् (जुस् replaced झि 3.4.108) = भिन्द्युस् ॥ अदा + सिच् + झि = अदा + o 2.4.77 + जुस् 3.4.10 = अदा + उस् = अदुः ॥ अ + या + झि = अ + या + उस् 6.4.111 = अयुः ॥ The उस् is also the substitute of झि in लिट् (Perfect) see 3.4.82. When the preceding vowel is not अ or आ, this rule does not apply. Thus the 3rd person plural of the Perfect of कृ is:- चकृ + उस् = चक्रुः ॥ So also from भी we have अबिभे + उस् = अबिभयुः ॥ The word अपदान्तात् 'not being final in a pada' does strictly speaking, serve no good purpose in this sutra. For the affix उस् can never be added to a Pada, it must always be added to a stem, that has not yet risen to the rank of a Pada. If उस्, however, be taken as the syllable उस् (whether an affix or part of an affix or not), then the limitation of अपदान्तात् becomes valid. Thus का + उस्रा = कोस्रा, का + उषिता = कोषिता ॥ Most likely this word has been read here for the sake of the subsequent sutra or because उस् syllable is taken here and not merely the affix उस् ॥
Śrīśa Chandra Vasu, The Ashtadhyayi of Panini (1897), via ashtadhyayi.com.