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 Ranbir mean?
A Sanskrit/Hindi compound of rana (रण, 'battle') and vira (वीर, 'hero, brave one'), giving 'a warrior brave in battle'.