6.1.152
प्रतिष्कशश्च कशेः
Operational rule vidhi
To the root कश् 'to go, to punish', is added the augment सुट् , when preceded by the preposition प्रति , the form being प्रतिष्कशः.
Word by word (padaccheda)
Substitute / term प्रतिष्कशः prathamā · ekavacanaIndeclinable च avyayaTarget कशेः ṣaṣṭhī · ekavacana
- Substitute / term Prathamā (1st case): in operational rules, the substitute or the thing introduced; in definitions, the term or its referent.
- Indeclinable An avyaya such as च "and", वा "optionally", न "not".
- Target Ṣaṣṭhī (6th case): names what gets replaced, "in place of X" (1.1.49 षष्ठी स्थानेयोगा).
Full reading
प्रतिष्कशः च कशेः
Pāṇini leaves out words that carry over from earlier sūtras. Expand to see the rule as a reader actually understands it.
कशेः → प्रतिष्कशः
Replace kaśeḥ with pratiṣkaśaḥ. Inherited words (anuvṛtti) may add further conditions.
Commentary
To the root कश् 'to go, to punish', is added the augment सुट् , when preceded by the preposition प्रति , the form being प्रतिष्कशः।
Verse
ग्राममद्य प्रवेक्ष्यामि भव मे त्वं प्रतिष्कशः ।
The word प्रतिष्कश is formed by adding अच् affix 3.1.134 to the root, with adding the prefix प्रति ॥ Thus ग्राममद्य प्रवेक्ष्यामि भव मे त्वं प्रतिष्कशः 'I shall inspect the town to-day, be thou my emissary'. The word प्रतिष्कशः means "a messenger, a herald, an emissary". Why do we say "to the root कश"? Observe प्रतिगतः कशां = प्रतिकशोऽश्वः 'a horse guided by the whip'. Here though कशा is derived from कश, yet the augment does not take place, because the augment comes to the root कश्, and not to a derivative word.
Śrīśa Chandra Vasu, The Ashtadhyayi of Panini (1897), via ashtadhyayi.com.