Declension table of ?adhivastra

Masculine	Singular	Dual	Plural
Nominative	adhivastraḥ	adhivastrau	adhivastrāḥ
Vocative	adhivastra	adhivastrau	adhivastrāḥ
Accusative	adhivastram	adhivastrau	adhivastrān
Instrumental	adhivastreṇa	adhivastrābhyām	adhivastraiḥ adhivastrebhiḥ
Dative	adhivastrāya	adhivastrābhyām	adhivastrebhyaḥ
Ablative	adhivastrāt	adhivastrābhyām	adhivastrebhyaḥ
Genitive	adhivastrasya	adhivastrayoḥ	adhivastrāṇām
Locative	adhivastre	adhivastrayoḥ	adhivastreṣu

Compound adhivastra -

Adverb -adhivastram -adhivastrāt