7.3.26
अर्धात् परिमाणस्य पूर्वस्य तु वा
Operational rule vidhi
Before a तद्धित affix having an indicatory ञ् , ण् or क् the वृद्धि is substituted for the first vowel of the second member, denoting a mass in its widest sense when the word अर्ध precedes it, but optionally for the first vowel of अर्ध.
Word by word (padaccheda)
Left context अर्धात् pañcamī · ekavacanaTarget परिमाणस्य ṣaṣṭhī · ekavacanaTarget पूर्वस्य ṣaṣṭhī · ekavacanaIndeclinable तु avyayaIndeclinable वा avyaya
- Left context Pañcamī (5th case): "after X", the operation applies to what follows (1.1.67 तस्मादित्युत्तरस्य). Also used for limits and sources.
- Target Ṣaṣṭhī (6th case): names what gets replaced, "in place of X" (1.1.49 षष्ठी स्थानेयोगा).
- Indeclinable An avyaya such as च "and", वा "optionally", न "not".
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
अर्धात् परिमाणस्य पूर्वस्य तु वा
Pāṇini leaves out words that carry over from earlier sūtras. Expand to see the rule as a reader actually understands it.
Commentary
Before a तद्धित affix having an indicatory ञ् , ण् or क् the वृद्धि is substituted for the first vowel of the second member, denoting a mass in its widest sense when the word अर्ध precedes it, but optionally for the first vowel of अर्ध।
As अर्धद्रौणिकम् or आर्धद्रौणिकम्, अर्धकौडविकम् or आर्धकौडविकम् with ठञ् 5.1.18. Why do we say when denoting a mass ? Observe आर्धक्रोशिकम् only (= अर्धक्रोशः प्रयोजनमस्य) ॥
Śrīśa Chandra Vasu, The Ashtadhyayi of Panini (1897), via ashtadhyayi.com.