कर्तृकरणयोस्तृतीया

Operational rule vidhi

In denoting the agent -- स्वतन्त्रः कर्ता (1.4.54), or the instrument -- साधकतमं करणम् (1.4.42), the 3rd case is used.

Word by word (padaccheda)

Right context - saptamī · dvivacanaSubstitute / term तृतीया prathamā · 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").
Substitute / term Prathamā (1st case): in operational rules, the substitute or the thing introduced; in definitions, the term or its referent.

Dotted words are technical terms. Hover or tap one to see its card.

Full reading

- तृतीया

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

Commentary

In denoting the agent -- स्वतन्त्रः कर्ता 1.4.54, or the instrument -- साधकतमं करणम् 1.4.42, the 3rd case is used.
Ex. देवदत्तेन कृतं 'done by Devadatta,' दात्रेण लुनाति 'he cuts with the sickle.' So also यज्ञदत्तेन भुक्तम्, परशुना छिनत्ति ॥

Vart:- The following words take the 3rd case. प्रकृति 'original,' प्राय 'almost,' गोत्र 'gotra,' सम 'equal,' विषम 'unequal,' द्विद्रोण, पंचक and साहस्र as प्रायेण याज्ञिकः, गार्ग्योऽस्मि गोत्रेण, समेन or विषमेण धावति, द्विद्रोणेन क्रीणाति &c.

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