Declension table of ?nityavyaya

Neuter	Singular	Dual	Plural
Nominative	nityavyayam	nityavyaye	nityavyayāni
Vocative	nityavyaya	nityavyaye	nityavyayāni
Accusative	nityavyayam	nityavyaye	nityavyayāni
Instrumental	nityavyayena	nityavyayābhyām	nityavyayaiḥ
Dative	nityavyayāya	nityavyayābhyām	nityavyayebhyaḥ
Ablative	nityavyayāt	nityavyayābhyām	nityavyayebhyaḥ
Genitive	nityavyayasya	nityavyayayoḥ	nityavyayānām
Locative	nityavyaye	nityavyayayoḥ	nityavyayeṣu

Compound nityavyaya -

Adverb -nityavyayam -nityavyayāt