A terrible portmanteau conflating domesticated fowl and the use of a pointing device designed for interactive personal computing.
Often the pejorative use of chicken (coward) is implied.
The clicken's primary habitat is within a preferred social network. However, friendless, free-range clickens will often migrate to blog forums to become a troll.
Clicken : Dude, I watched 25 police brutality videos today and posted them on Facebook.
Dude (bleeding) : You suck. I was IN them.
Clicken : Ah. ...I'll tag you and send them to your lawyer.
Dude (bleeding) : If my spleen wasn't ruptured, I'd hug you.