2.4.33
एतदस्त्रतसोस्त्रतसौ चानुदात्तौ
Operational rule vidhi
In the room of एतद् in the case of re-employment there is the substitution of the gravely accented अश् when the affixes त्र -- सप्तम्यास्त्रल् (5.3.10) and तस् -- पञ्चम्यास्तसिल् (5.3.7) follow, and the affixes त्र and तद् are अनुदात्त (gravely accented) also.
Word by word (padaccheda)
Target एतदः ṣaṣṭhī · ekavacanaRight context त्र- तसोः saptamī · dvivacanaSubstitute / term त्र- तसौ prathamā · dvivacanaIndeclinable च avyayaSubstitute / term prathamā · dvivacana
- Target Ṣaṣṭhī (6th case): names what gets replaced, "in place of X" (1.1.49 षष्ठी स्थानेयोगा).
- 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.
- Indeclinable An avyaya such as च "and", वा "optionally", न "not".
Dotted words are technical terms. Hover or tap one to see its card.
Full reading
एतदः त्र-
Pāṇini leaves out words that carry over from earlier sūtras. Expand to see the rule as a reader actually understands it.
एतदः → त्र-
Replace etadaḥ with tra-tasau anudāttau when tra-tasoḥ follows. Inherited words (anuvṛtti) may add further conditions.
Commentary
In the room of एतद् in the case of re-employment there is the substitution of the gravely accented अश् when the affixes त्र -- सप्तम्यास्त्रल् 5.3.10 and तस् -- पञ्चम्यास्तसिल् 5.3.7 follow, and the affixes त्र and तद् are अनुदात्त (gravely accented) also.
Thus अत्र 'here,' and अतस् 'hence' in the following :- एतस्मिन् ग्रामे सुखं वसामः ; अथो अत्र युक्ता अधीमहे । 'We live in this (etasmin) village, happily, therefore let us read with full devotion in this (atra).' एतस्माच्छात्राच्छन्दोऽधीष्व, अथो अतो व्याकरणमप्यधीष्व । 'Learn from this student Prosody and also learn from him Grammar.' By rule 5.3.5 अश् is declared to be the substitute of एतद्; its repetition here is to indicate that this अश् of anvadesa is anudatta.
Śrīśa Chandra Vasu, The Ashtadhyayi of Panini (1897), via ashtadhyayi.com.