As sww says above. 용(用) means "for", "use", etc. Here's an example when it is used in a compound word. 학생용 = for student use (e.g., not for professional use) It can have various translations, and " 위해" does seem quite close as a synonym. 용으로 = as, for, as a way of, etc.

시간 때우기 용으로 읽었던

Meaning "I can kill time for read"

용 => ~위해(for(?))