A new video of someone, which has been generated from animating a static image with another video, in order to make the person in the static image say funny or stupid things
Dude1: Hey dude, did you see that video of Oprah singing Frank Sinatra?
Dude2: No dude, that was a fakerface!
Dude1: Oh dude, these fakers are funny!
When someone leaves their Facebook account logged in or shares their login details with someone else at which point someone makes posts to said person's account without their knowledge.
"Bill just got facejacked. That guy gave me his login credentials for Facebook so I wrote on his wall and updated his status."