अचो ञ्णिति

Operational rule vidhi

An अजन्त अङ्ग undergoes वृद्धि when followed by a णित् or a ञित् प्रत्यय.

Word by word (padaccheda)

Target ṣaṣṭhī · ekavacanaRight context ञ्णिति 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").

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

ञ्णिति

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

Commentary

Before the affixes having an indicatory ञ् or ण् , वृद्धि is substituted for the end-vowel of a अङ्ग (stem).
Thus एकस्तण्डुलनिचायः, 3.3.20 द्वौ शूर्पनिष्पावौ, कारः and हारः (with धञ्); गौः, गावौ, गावः, सखायौ, सखायः where the case-endings are णित् by 7.1.90, 7.1.92. जैत्रम्, यौत्रम् with the Unadi ष्ट्रण् from जि and यु ॥ च्यौत्नः with त्नण् and means 'strength'. It is an obsolete Vedic word.

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