Pāṇini sūtras

ṣ is the substitute of that visarga, which is preceded by i or u and is followed by an affix beginning with a hard guttural or a labial.

German Geht dem Visarjanīya ein i oder u voran, so tritt vor den genannten Suffixen ṣ an die Stelle desselben. (39)

1. i+ṇaḥइ+णः

   Part	Lexeme	Sandhi form	Meaning	Stem + termination
   iइ	iइ	iइ	ikāraइकार	iइ
   ṇण्	ṇण्	ṇaḥणः	NaNअ	ṇण् + plus aḥअः

2. ṣaḥषः

   Part	Lexeme	Sandhi form	Meaning	Stem + termination
   ṣष्	ṣaष	ṣaḥषः	ṣakāraषकार	ṣष् + plus aḥअः

Anuvṛtti

1. visarjanīyasyaविसर्जनीयस्य 8·3·34

   Part	Lexeme	Sandhi form	Meaning	Stem + termination
   vव्	visarjanīyaविसर्जनीय	visarjanīyasyaविसर्जनीयस्य	visarga	visarjanīyविसर्जनीय् + plus asyaअस्य

2. ku+pvoḥकु+प्वोः 8·3·37

   Part	Lexeme	Sandhi form	Meaning	Stem + termination
   kक्	kuकु	kuकु	guttural	kक् + plus uउ
   pप्	puपु	pvoḥप्वोः	labial consonant	pप् + plus voḥवोः

3. a+pada+ādauअ+पद+आदौ 8·3·38

   Part	Lexeme	Sandhi form	Meaning	Stem + termination
   aअ	aअ	aअ	not	aअ
   pप्	padaपद	padaपद	word	padपद् + plus aअ
   āआ	ādiआदि	ādauआदौ	first syllable	ādआद् + plus auऔ