1. To successfully pull off some sort of a prank involving calling another person's cell phone, usually from a masked number (for instance, via relay).
2. To be struck by a cell phone, preferably in the face, in such a forceful manner that one could only it as describe as being owned.
"Hey, I just relayed Dan, from work, and left him a sweet message."
"What'd you say?"
"I had the operator tell him I was from the corporate office, and if he wanted a promotion then he needs to help me wipe my butt, and then I layed down a nice freestyle about my favorite vegetables."
"Man, that's ridiculous. He'll know it was you."
"No way, I totally cellphowned him."
Clpwned is when someone gets knocked out by a slap from a friend on a dare, and all his friends laugh at him as his unconscious body falls on a bag of empty beer cans.
Originates from Tennis lore. Getting “cellphoned” is when one player hits a solid crushing winner to set the tone for the rest of the match. Cellphoning an opponent increases the playersstreet cred.
Also used in daily life when something one does exceeds the extraordinary.