fakephoning 

The practice of pretending you are on a cell phone call in order to avoid an unpleasant or awkward encounter with a person who has ventured into your immediate area. Can also be used in the car when recognizing someone on the street or in another vehicle.

"Dude, I saw Cynthia at the mall last night. I tried to avoid her but she came up and asked why I never called her back."

"You ought to try fakephoning. I pull out my cell whenever I see someone I don't want to talk to."

fakephoning by Commentator X September 25, 2009