Declension table of ?adhivastra

Neuter	Singular	Dual	Plural
Nominative	adhivastram	adhivastre	adhivastrāṇi
Vocative	adhivastra	adhivastre	adhivastrāṇi
Accusative	adhivastram	adhivastre	adhivastrāṇi
Instrumental	adhivastreṇa	adhivastrābhyām	adhivastraiḥ
Dative	adhivastrāya	adhivastrābhyām	adhivastrebhyaḥ
Ablative	adhivastrāt	adhivastrābhyām	adhivastrebhyaḥ
Genitive	adhivastrasya	adhivastrayoḥ	adhivastrāṇām
Locative	adhivastre	adhivastrayoḥ	adhivastreṣu

Compound adhivastra -

Adverb -adhivastram -adhivastrāt