What does Hiranya mean?
From Sanskrit 'hiranya' (हिरण्य) meaning 'gold'; the related adjective 'hiranmaya' means 'golden'. Dictionary-level 'gold' meaning is well attested.
What does Naga mean?
From Sanskrit नाग (naga) 'snake, serpent', also denoting the semi-divine serpent beings (nagas) of Hindu and Buddhist lore. Note: classical Sanskrit lexicons record a secondary established sense 'elephant', and the deeper etymology of the word is itself uncertain; the primary and relevant meaning here is 'serpent'.