where you get a massive NARB (no apparent reason boner) in a public place, and the only way to make it go down is by ejaculation. Therefore, you must proceed to put your hand in your pocket, grip your penis, begin to jerk self off, and continue process until desired result is achieved.
dude1: what the fuck bro i just got a NARB!?
dude2: just pocket pull it man.
UK slang: "I've got nothing." or "Nothing came of it."
I think it comes from somethinglike 'couldn't even get a drink at the pub, just left with some stolen mustard pacs'.
Did you get the (job/girl/money/news)?... Nah; "pocketful of mustard."
A pocket full of drugs of some type, typically weed, or some other type, since hippies associate themselves with the sun for some reason.
"Hey Bob, that football captain guy is sooo hot that I get a pocketful of sunshine when I see him."
"what? You get a pocketful of drugs from him?"
"No, he just makes me sooo hot..."
"Where'd you get that definition? From that first definition of pocketful of sunshine that retard made?