हलस्तद्धितस्य

Operational rule vidhi

The य् of a तद्धित affix when preceded by a consonant and penultimate in a अङ्ग (stem), is elided before the feminine ई.

Word by word (padaccheda)

Left context pañcamī · ekavacanaTarget ṣaṣṭhī · ekavacana

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).

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

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

Commentary

The य् of a तद्धित affix when preceded by a consonant and penultimate in a अङ्ग (stem), is elided before the feminine ई।
The anuvritti of "taddhita" ceases, because of its mention in the next sutra. Hence this sutra applies to feminine ई only. As गार्गी, वात्सी from गार्ग्य and वात्स्य ॥ Why do we say 'when preceded by a consonant'? Observe कारिकेयी ॥ Why do we say 'of a Taddhita'. Observe वैद्यस्य भार्या = वैद्यी ॥

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