ERAT 

A sound from the 1987 Technos video game Super Dodgeball.

The sound comes from one player being hit with tremendous force by the other with the dodgeball. The player being hit is blown off the playing field.

The sound is attributed to some one who tells a lame ass joke.

Matt: Dude, wanna hear a dirty joke?

Chris: What

Matt: Chris fell in the mudd

Chris: ERAT

ERAT by TBurger Man September 30, 2006

Erat 

A word used in place of "Alright", also used with "Tat" instead of "Tight".

"Well then erat"
"That's Tat Erat!"
"I'll talk to you later" "Erat"

Erat by agr33n3rfilm February 22, 2005

Erat 

When you are a rat online.

Søren: yoo, Mads, Asgar has fucked your girl.
Asgar: Damn, you erat.
Everybody else: Get this erat out the group call

Erat by IHaveStage3TerminalCancer May 12, 2022

quod erat demonstrandum

Originating from the Greek analogous hóper édei deîxai (ὅπερ ἔδει δεῖξαι), meaning "which had to be demonstrated". The phrase is traditionally placed in its abbreviated form (Q.E.D.) at the end of a mathematical proof or philosophical argument. Phrase synonymous with "Quite Easily Done."

∫|Ψ(x, t)|² dx (from -infinity to infinity)= e^(2Γt/ħ) ∫|ψ|²dx(from -infinity to infinity)
The second term is independant of t, therefore Γ=0 & ∫|Ψ(x, t)|² dx (from -infinity to infinity)=∫|ψ|²dx(from -infinity to infinity)=1 {Normalized}
Q.E.D. "quod erat demonstrandum"

quod erat demonstrandum by justinbonito October 31, 2013

quod erat demostratem 

ego sum discipulus optimus. ego non sum discipulus malus. saxtus est discipulus malus.
"Veto!"

Oh right, and it's a math term. It means "what was to be demonstrated", used in proofs of innumerable math proofs.

x=-b+-root(b^2-4ac)/2a

QED (Quod Erat Demonstratem)

quod erat demostratem by [Dunbar]** February 11, 2004

Erratas/Eratas 

Erratas is a myth on the internet, that describes a system used by large corporations to aim for specific victims, to copyright strike. According to the myth, the system will delete any reference of itself from the internet. Not much is known about the myth, but most suspect that it is just a story, and nothing serious. Sometimes, people use Eratas to go under the system.

Person 1: Have you heard of Erratas/Eratas?
Person 2: Yeah, but I’m pretty sure it’s fake.

Erratas/Eratas by Krotokoic October 20, 2019

to in-sink erate 

to put something down a garbage disposal

Ellen is in-sink erating the banana skins.

It is not a good idea to in-sink erate beer bottle caps.

to in-sink erate by Girls 124 March 18, 2011