modmail

noun2

1. •
   A messaging system on Reddit and similar discussion sites, used for communication between moderators and other users.

   • They asked for simple things like updates to their “modmail,” the internal message tool that moderators use to manage their groups. — 2018
2. •
   A message sent through modmail.

   • Yet they still faced pressure from many their community to join the blackout: “we eventually released the statement after we received dozens of modmails and posts on both subreddits.” — 2019