शुष्कधृष्टौ

Operational rule vidhi

Also शुष्क and धृष्ट have acute on the first syllable.

Word by word (padaccheda)

Substitute / term शुष्क- धृष्टौ prathamā · dvivacana

Substitute / term Prathamā (1st case): in operational rules, the substitute or the thing introduced; in definitions, the term or its referent.

Dotted words are technical terms. Hover or tap one to see its card.

शुष्क-धृष्टौ

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

Also शुष्क and धृष्ट have acute on the first syllable.
These are non-Names. Thus शुष्कः and धृष्टः ॥

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