Declension table of ?kupa

Masculine	Singular	Dual	Plural
Nominative	kupaḥ	kupau	kupāḥ
Vocative	kupa	kupau	kupāḥ
Accusative	kupam	kupau	kupān
Instrumental	kupena	kupābhyām	kupaiḥ kupebhiḥ
Dative	kupāya	kupābhyām	kupebhyaḥ
Ablative	kupāt	kupābhyām	kupebhyaḥ
Genitive	kupasya	kupayoḥ	kupānām
Locative	kupe	kupayoḥ	kupeṣu

Compound kupa -

Adverb -kupam -kupāt