you dont know jack shit 

you dont know jack shit a word meaning you know nothing or are too stupid to figure it out

dude whats an electric car

man you dont know jack shit you are too stupid to know what an electric car is unless you get ran over by one

you dont know jack shit by littlejimmie January 24, 2019

Reverse Jack Syndrome 

Reverse Jack Syndrome (RJS) is the opposite of the syndrome Robin Williams had in the movie "Jack." His character's affliction caused him to grow physically old while still being young in terms of years - RJS is the reverse of this. A person with RJS is relatively young and young-looking but acts and feels as if he/she is approximately 70 years old. For example, a person with RJS is almost always cold, regardless of temperature (this leads to wearing unfashionable slippers at home); has trouble hearing, thus the TV volume is always very loud; likes food commonly associated with old people, for ex. meatloaf and salisbury steak; has trouble with new technology; has preferences in terms of music, books, and culture in general that are usually linked with old folks; and is generally crabby, with the demeanor of a cranky old person.

"Jimmy, why is it 90 degrees in here? WTF?"

"Its cold in here."

"Ah, must be the Reverse Jack Syndrome acting up again."

Reverse Jack Syndrome by Drew D. from Kansas August 6, 2007

A jack dane 

When you projectile poo all over the body of somebody's mum at their funeral

Person 1: did you hear what happend last week?
Person 2: no what happend
Person 1:that lad over there did a jack dane at Henry's mums funeral lmao

A jack dane by Gay lord69 November 27, 2020

E-Wank/E-Jack Off 

The action of touching ones genitalia and jacking off to your own works or your own art, especially in front of everyone digitally.

Boy 1: *jacks off to his typed out role play on a forum*
Girl 1/Boy 1’s Alt: *roleplaying by himself*
Boy 2: I checked your IP address, and that “girl” is you, mate. You’re a total E-Wank/E-Jack Off.

E-Wank/E-Jack Off by Collective Reasoning October 14, 2019

Corn Jack 

Australian delicacy. One of the finest items available on the fish and chip shop menu. Consists pretty much of cream corn in a pastry/batter outer. Deep Fried. Absolutely delicious.

Customer: "Can i please have one Corn Jack?"
Fish and Chip Shop guy: "Certainly, that'll be $1.80, and stop calling me Jack".

Corn Jack by Jack the Corn Jack January 24, 2005

Spring Heeled Jack 

A demon of English folklore who was first reported in the UK in the year 1837.

According to legend Spring Heeled Jack only appears at night abducting people, though he abducts women most of the time.

He is a feared demon who causes the disapearance of many; It's unknown what happens to his victims.

Spring Heeled Jack is said to look like a mustached gentleman wearing a suit, shoes, tie, gloves, top hat, and a monicle.

Spring Heeled Jack is said to jump very high and that he can leap through great distaces which gives him the appearance of flight.
(hence the name Spring Heeled Jack)

It is believed that he has super jumping abilities, others claim that his shoes have springs.

It is also belived that salt is his weakness, it is said that salt can turn him into stone.

In the legend, water can restore Jack from being a stone statue.

I saw Spring Heeled Jack Jumping over the entire neighborhood.

Spring Heeled Jack by SuperDinner4 March 14, 2011

captain jack 

captain jack is a street name for heroin
an example of this is billy joel's song "captain jack"

"Captain jack will get you by tonight, take you to your special island, Captain jack will get you by tonight, just a little push and you'll be flying"

captain jack by matthew D January 7, 2009