Declension table of ?nirnāśana

Neuter	Singular	Dual	Plural
Nominative	nirnāśanam	nirnāśane	nirnāśanāni
Vocative	nirnāśana	nirnāśane	nirnāśanāni
Accusative	nirnāśanam	nirnāśane	nirnāśanāni
Instrumental	nirnāśanena	nirnāśanābhyām	nirnāśanaiḥ
Dative	nirnāśanāya	nirnāśanābhyām	nirnāśanebhyaḥ
Ablative	nirnāśanāt	nirnāśanābhyām	nirnāśanebhyaḥ
Genitive	nirnāśanasya	nirnāśanayoḥ	nirnāśanānām
Locative	nirnāśane	nirnāśanayoḥ	nirnāśaneṣu

Compound nirnāśana -

Adverb -nirnāśanam -nirnāśanāt