Another word for your cell phone. Meaning that it is used to pick up grease (aka women, guys, booty call, etc...). Often used to describe a phone that gets ridiculous amounts of calls, texts and picture messages resulting from hitting on people and greasing them up like a boss.
"Heey, why didn't you pick up the grease horn last night?"
"Sorry man, it wasn't working, there was much too much grease so it was pooched for the night"
"Ahhh, I get it. You salty dawg you!!!"