अव्ययादाप्सुपः

Operational rule vidhi

The आप्-प्रत्ययाः and the सुप्-प्रत्ययाः attached to an अव्यय are removed by doing a लुक्.

Word by word (padaccheda)

Left context pañcamī · ekavacanaTarget आप्- 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

आप्-

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

Commentary

There is लुक् elision of आप् (the feminine termination) and सुप् (the case-affixes) after an अव्यय or indeclinable.
Thus, तत्र शालायाम् 'in that hall'. Here the Indeclinable तत्र 'there,' does not take the feminine termination, although it is equivalent to तस्याम् 'in that.' So also कृत्वा 'having done' हित्वा &c. Here the case affix is elided.

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