What does Rohan mean?
From Sanskrit rohana (रोहण), 'rising, ascending, growing'. Some sources also give 'sandalwood'; the core attested sense is 'ascending/growth'. (Note: an unrelated Irish name Rohan/Rowan also exists.)
What does Arjun mean?
From Sanskrit arjuna (अर्जुन), 'white, bright, silvery, clear'. Best known as the heroic third Pandava prince and Krishna's friend in the Mahabharata; the literal root sense is 'shining/white' rather than 'warrior'.