(noun) Any dog that can catch a frisbee or jump more than one and a half times its own height. These athletic feats of agility distinguish certain dogs as ninjas instead of regular shit factories.
1.(Noun) A term used for when you don't want to talk to someone but they instant message you over facebook. You then proceed to not let your presence known, and go into a ninja hiding position.
2. (Noun) A term for someone who does not appear to be online facebook, but goes around and comments on everyone'swall.
3. (Noun) A term for someone who is not in the social networking exchange known as facebook, but is tagged in pictures and messages.
"Hey Daniel ;) "
*Oh God, do I really have to talk to her?*
*5 minutes later with no response*
"Daniel, stop being a ball-less facebook ninja and talk to me!"
Kelly commented on Daniel's status
"What? Kelly's online? But she's not on my 'online' list.... what a facebook ninja."
*looking at a friend's picture with a hot chick in it*
"Oh wow, who is SHE?"
*searches for her, can't find her*
"Dang it! She's a stupid facebook ninja! Gah!"