What does Ishita mean?
From the Sanskrit ईशिता (īśitā), 'superiority, supremacy, lordship' — one of the eight siddhis (mystic powers) in yogic tradition. Commonly rendered 'one who desires to rule' or 'preeminent'.
What does Nishka mean?
From the Sanskrit निष्क (niṣka), an ancient gold coin, and by extension a golden necklace or ornament — attested in the Manusmriti and other classical texts. Popular 'pure/honest' glosses on name sites are not supported by the classical sources.