Pāṇini sūtras

The substitution of dat for danta is optional in a Bahuvrûhi, when it is preceded by a word ending in agra or by śuddha, śubhra, vṛṣa and varāha

1. agra+anta+śuddha+śubhra+vṛṣa+varāhebhyaḥअग्र+अन्त+शुद्ध+शुभ्र+वृष+वराहेभ्यः

   Part	Lexeme	Sandhi form	Meaning	Stem + termination
   aअ	agraअग्र	agraअग्र	agra [word]	agrअग्र् + plus aअ
   aअ	antaअन्त	antaअन्त	anta [word]	antअन्त् + plus aअ
   śश्	śuddhaशुद्ध	śuddhaशुद्ध	śuddha [word]शुद्ध [wओर्द्]	śuddhशुद्ध् + plus aअ
   śश्	śubhraशुभ्र	śubhraशुभ्र	śubhra [word]शुभ्र [wओर्द्]	śubhrशुभ्र् + plus aअ
   vव्	vṛṣaवृष	vṛṣaवृष	vṛṣa [word]वृष [wओर्द्]	vṛṣवृष् + plus aअ
   vव्	varāhaवराह	varāhebhyaḥवराहेभ्यः	varāha [word]वराह [wओर्द्]	varāhवराह् + plus ebhyãएभ्य̃

2. caच

   Part	Lexeme	Sandhi form	Meaning	Stem
   cच्	caच	caच	besides	caच

Anuvṛtti

1. samāsa+antāḥसमास+अन्ताः 5·4·68

   Part	Lexeme	Sandhi form	Meaning	Stem + termination
   sस्	samāsaसमास	samāsaसमास	Sanskrit compound	samāsसमास् + plus aअ
   aअ	antaअन्त	antāḥअन्ताः	end	antअन्त् + plus āMआM

2. bahuvrīhauबहुव्रीहौ 5·4·113

   Part	Lexeme	Sandhi form	Meaning	Stem + termination
   bब्	bahuvrīhiबहुव्रीहि	bahuvrīhauबहुव्रीहौ	bahuvrīhiबहुव्रीहि	bahuvrīhबहुव्रीह् + plus auऔ

3. datṛदतृ 5·4·141

   Part	Lexeme	Sandhi form	Meaning	Stem + termination
   dद्	datṛदतृ	datṛदतृ	datṛदतृ	datदत् + plus ṛऋ

4. vibhāṣāविभाषा 5·4·144

   Part	Lexeme	Sandhi form	Meaning	Stem + termination
   vव्	vibhāṣविभाष्	vibhāṣāविभाषा	option	vibhāṣविभाष् + plus āआ