Declension table of ?vivatsa

Masculine	Singular	Dual	Plural
Nominative	vivatsaḥ	vivatsau	vivatsāḥ
Vocative	vivatsa	vivatsau	vivatsāḥ
Accusative	vivatsam	vivatsau	vivatsān
Instrumental	vivatsena	vivatsābhyām	vivatsaiḥ vivatsebhiḥ
Dative	vivatsāya	vivatsābhyām	vivatsebhyaḥ
Ablative	vivatsāt	vivatsābhyām	vivatsebhyaḥ
Genitive	vivatsasya	vivatsayoḥ	vivatsānām
Locative	vivatse	vivatsayoḥ	vivatseṣu

Compound vivatsa -

Adverb -vivatsam -vivatsāt