What does Nirav mean?
From the Sanskrit निरव (nirava), 'soundless, still', formed from nir- ('without') + rava ('sound, noise') — hence tranquil stillness. A genuine, if less common, classical formation.
What does Raja mean?
From Sanskrit 'rajan' (nominative 'raja'), meaning 'king', ultimately from a Proto-Indo-European root meaning 'to rule, to straighten'. (Note: the identically-spelled Arabic 'Raja' is an unrelated feminine name meaning 'hope'.)