It is a korean slang word which means someone who is eccentric and wacky. It is not a word meant to insult a person, instead it is something which is used to complement him/her.

This is most commonly used to describe Korean celebrities with a strong personality. It may also be used to indicate that a person has a very strong individuality or a unique personality.

This is derived from ordinary people being "3d", so a person which is so quirky and thinks outside the box is considered "4d" or 4-dimensional.
Victoria is so 4D! She acts like a kid and yet she dresses up gorgeous! jjang!

I knew my friend was 4D! She always introduces out-of-this-world topics.

Daebak! His 4dness is starting to rub on me!
by Justox Dizaola December 1, 2010
An additional dimension to the traditional three: length, width, depth. It is most often associated with time, although it could very well represent other variables, such as temperature or attraction, as it is, literally, just another quality to describe something.

There are conjectures that there may be ten total dimensions, even more, or even an infinite amount. The thought concerning dimensions past 3D is generally in the realm of the theoretical.
Since we see 2D in 3D (what you actually see is a 2D image), we would see true 3D when looking from 4D.
by Anon Nymous December 22, 2006
4D in this case is having your senses heightened, so you don't see things in 3D as you usally do, you see them in 4D hear them smell them taste them touch them. it happens when you smoke alot of weed, just before you whitey mainly, so basically being real stoned.
you seem to be able to read body language better, and figure things out, but way too lazy to move, and in my case my limb's such as my legs and arms, seem to move to the sound of music without my control.
everything is warm in 4D and you generally feel good, but you can ffeel down when you realise the faults of your friends, and what makes you feel down is that your thinking about your friends in this kinda way
but end of it's all good.

the term for this 4D orginated in wolverhampton, by a guy called amit
Stax:"Amit are you ok?"
Amit"no everythings 4D"

Emma:"Amit you getting 4D today?"
Amit: "hopefully :D"
by thethongofanime August 9, 2005
Possessing a fourth-dimensional consciousness, also known as "Einsteinian spacetime" consciousness, in which the past, present, and future are experienced simultaneously. Stage of developing human consciousness as a result of surviving "Sitchin Shock," the ontological shock of the realization his basis thesis is true.
"Dude, I passed the acid test, slid through the open door, and now I'm like totally 4D"
by came with them May 30, 2007
Four dimensions. They are length, width, depth, and time. 6 other dimensions also exist, but they are confined to upper-level quantum physics that you wouldn't understand.
If a person flies in a airplane his whole entire life, he will live longer because he is traveling through time (dead serious!!!)
by Meh June 23, 2004
4D: 40 0z of booze Motha' Fucka'!
"Yo bitch! Stop by the quik E mart and Pick me up a 4D and some Menthols. Peace"
by Potato"s O'Brien April 2, 2005
a simp that only listens to to a girl that is on the same Dimentional plane. like if there are two boys and one girl the simp only responds to her and not to you because you are a normal human that is on a 3D plane.
Her: Let's go to the new icecream place
You: They don't have any good flavors now
Him:Yeah they must have good flavors

You: What did I just say
Him: I will pay for you
Her:But he just said they weren't good
Him: Did you say something
You: Its fine you are just on a 4D plane
by SWAGTRUTH June 6, 2021