adviser (n.)

• admonisher
• announcer
• annunciator
• authority
• buttinsky
• channel
• cicerone
• communicant
• communicator
• confidant
• confidante
• consultant
• counsel
• counselor
• expert
• gossipmonger
• grapevine
• guide
• informant
• informer
• instructor
• interviewee
• kibitzer
• meddler
• mentor
• monitor
• mouthpiece
• nestor
• newsmonger
• press
• publisher
• radio
• reporter
• source
• spokesman
• teacher
• television
• teller
• tipster
• tout
• witness