consultant (n.)

• adept
• admonisher
• adviser
• advisor
• artisan
• artist
• attache
• authority
• buttinsky
• confidant
• connoisseur
• counsel
• counselor
• craftsman
• diplomat
• diplomatist
• doctor
• expert
• graduate
• guide
• instructor
• journeyman
• kibitzer
• marksman
• meddler
• mentor
• monitor
• nestor
• physician
• politician
• pro
• professional
• professor
• savant
• shark
• sharp
• specialist
• statesman
• teacher
• technician