Traditional Definition: A shaped piece of fabric attached inside or outside a garment and forming a pouch used esp. for carrying small articles.
2. I keep my keys in my right pocket.
The origin of the name pocket refers to the first lines of the song "The Good Times Are Killing Me" by Modest Mouse.
Modest Mouse #2: "Ya, Erik's got those pockets."
"I will be over in twenty minutes with a gram of Sour D and a pocket."
"I'm going to Quik Trip to pick up a pocket"
Bro 2: "Aww come on man it was an accident"
Person 2: "Wassup bro?"
Person 1: "Whoa.....oh hi"
Person 2: "Whats in your pocket bro?"
Person 1: "Uhh...um......nothing."