Possible Clues:

• Date with an M.D
• Rendezvous of a sort (abbr.)
• Schedule's meeting entry: Abbr
• iCal entry
• Engagement calendar info: Abbr
• Date-book entry: Abbr
• Event on a doctor's calendar (abbr.)
• What your personal asst. might set for you (you have a personal asst., right?)
• Scheduled dr. visit
• HMO visit