Declension table of ?siṣīvvas

Masculine	Singular	Dual	Plural
Nominative	siṣīvvān	siṣīvvāṃsau	siṣīvvāṃsaḥ
Vocative	siṣīvvan	siṣīvvāṃsau	siṣīvvāṃsaḥ
Accusative	siṣīvvāṃsam	siṣīvvāṃsau	siṣīvuṣaḥ
Instrumental	siṣīvuṣā	siṣīvvadbhyām	siṣīvvadbhiḥ
Dative	siṣīvuṣe	siṣīvvadbhyām	siṣīvvadbhyaḥ
Ablative	siṣīvuṣaḥ	siṣīvvadbhyām	siṣīvvadbhyaḥ
Genitive	siṣīvuṣaḥ	siṣīvuṣoḥ	siṣīvuṣām
Locative	siṣīvuṣi	siṣīvuṣoḥ	siṣīvvatsu

Compound siṣīvvat -

Adverb -siṣīvvas