A meme that involves isolating one face within a group photo and photoshopping it over every person’s face.
Person A: Someone guy behind us photobombed our beach pic, but his face was so hilarious that I photoshopped it on all of our faces. Person B: OMG no way let me see! *shows* Person B: DUDE what an awesome facebomb, get that on 4chan ASAP!
By chromechisel49
To comment, like, and do anything to make sure you've left your presence on someone's facebook page Usually ending in 99 notifications when the user (victim) logs in. All from you!
a) I logged into my account only to find I'd been facebombed! b) Hay Mikey, Yeah Jamie?, Let's Facebomb Kat's profile! Shot Facebomb!
By Jynxd1
to cover someone else's facebook wall with comments; to become the only poster on a facebook wall.
"I posted like, fifteen messages on her wall today! It was a total facebomb!"
By pindik
The act of leaving wall posts on someone's facebook page when they forgot to log out of their account while you pretend to be them.
"I facebombed my sister so bad the other day. I posted that her older sister (me) was the coolest person she had ever met and that everyone wanted to be like her."
By Sub1ime
To comment excessively on another person's Facebook page, usually all at one time.
Benny: Dude, do you think she's knows I'm interested in her? Sebastien: Well, you commented on every single picture in her profile album and left five comments on her wall in the past five minutes. I think she knows. Facebomb much?
By Starrynight1979