I've done it for 13 years so I am likely the best one to attempt to define it.

• Reports to Internet Brands who owns FlyerTalk
• Selects and manages all moderators
• Responsible for training program for new moderators
• Chooses senior moderators
• Determines who are company reps and designates them as such
• Receives appeals of suspensions
• Receives comments directly from members
• Deals with handle changes (permitted once for those with less than 500 posts)
• Adds In Memoriam to member profile for those who have left us
• Has a forum, The Suggestion Box, where members can suggest improvements for the board
• Decides when to add new forums after member input
• Works with a team of moderators to be sure that the FlyerTalk rules are up to date; gets Internet Brand approval of any changes
• Runs workshops for moderators to train them and to discuss how to improve; a recent topic was ChatGT

There's a fair bit of nonstandard activity but this gives a sense of what goes on day in and day out.