AFK

From CoCWiki

AFK is an acronym that means "Away From Keyboard". It is commonly used to represent those who are away in the lobby and in game rooms. You will find AFK's many times and they have the little clock symbol that shows they're AFK.

As these people take up space in the game rooms, there is a possible auto-kick feature in the future that will kick people who have been AFK after a while so there is more room for others to play.

The clock symbol disappears when the user moves their mouse over the window.

Players with clocks with their name are afk (As shows in red squares)