8.3.113
सेधतेर्गतौ
Operational rule vidhi
The ष् substitution does not take place in the स् of the verb सेध when the meaning is that of moving.
Word by word (padaccheda)
Target सेधतेः ṣaṣṭhī · ekavacanaRight context गतौ saptamī · ekavacana
- 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").
Full reading
सेधतेः गतौ
Pāṇini leaves out words that carry over from earlier sūtras. Expand to see the rule as a reader actually understands it.
Commentary
The ष् substitution does not take place in the स् of the verb सेध when the meaning is that of moving.
Thus अभिसेधयति गाः, परिसेधयति गाः ॥ This is an exception to 8.3.65.
Why do we say 'when meaning to drive'? Observe शिष्यमकार्यात्प्रतिषेधयति ॥ Here the sense is that of preventing or prohibiting.
Śrīśa Chandra Vasu, The Ashtadhyayi of Panini (1897), via ashtadhyayi.com.