Gírias (J) Slang

jack around [possibly offensive]: waste time.
"Will you please stop jacking around?"

jam, in a (1): trouble.
"If you're in a jam, I promise to help you."

jam (2): improvise (musically).
"I'd love to jam with Bon Jovi!"

jamming, to be : going well.
"The cafe is really jamming!"

jerk: stupid or annoying person.
"How could you go out with such a jerk?"

jillion: an immense number.
"Do you really have a jillion problems?"

jock: someone good at sports.
"I've never been much of a jock."

john: toilet.
"Where's the john?"

Source: http://www.eslcafe.com/slang/j.html

Gírias (I) Slang

icky: unpleasant.
"The food is really icky in the school cafeteria."

I.D.: identification.
"If you want to order a beer, you'll need your I.D."

I'm outta here: I'm leaving; I'm departing.
"Sorry, but I'm outta here, dude."

in: fashionable.
"Ray-Ban sunglasses are really in now."

ivories: teeth.
"Tom Cruise has really beautiful ivories."


Source: http://www.eslcafe.com/slang/i.html