Skip to main content
Urban Dictionary Merch
Your favorite words on things you can wear, drink from, read, or give to a friend.
The Urban Dictionary Store sells gifts you’ll have to explain.

does 9.99999999 = 10? 

like if you think it is and dislike if you think it is not
does 9.99999999 = 10?

(sqrt(cos(x))*cos(999999999999999999999999999999999999999999999999999 x)+sqrt(abs(x))-0.7)*(4-x*x)^0.01, sqrt(9-x^2), -sqrt(9-x^2) from -4.5 to 4.5

Don't try solving it, just put it into google, it makes a nice heart!

idea from some other guy
thanks
(sqrt(cos(x))*cos(999999999999999999999999999999999999999999999999999 x)+sqrt(abs(x))-0.7)*(4-x*x)^0.01, sqrt(9-x^2), -sqrt(9-x^2) from -4.5 to 4.5

999999999888888887777777666666555554444333221

When you've tried each combination of letters possible, so you decide to go through every number combination possible.

Usually when bored during work and or school
Guy 1 : instead of being productive, why not put in 999999999888888887777777666666555554444333221 into the google search bar?

Guy 2 : good idea, good idea.

9999999999999999999999 

too manny 9s too mannnnnnnnnnnnyyyyyyyyyy
your iq is (not) 9999999999999999999999
9999999999999999999999 by de retard January 25, 2021

(sqrt(cos(x))*cos(999999999999999999999999999999999999999999999999999 x)+sqrt(abs(x))-0.7)*(4-x*x)^0.01, sqrt(9-x^2), -sqrt(9-x^2) from -4.5 to 4.5

On May 15, 2020, a user known as "giant salamanders eat paint" said, "Don't try solving it, just put it into google, it makes a nice heart!

idea from some other guy
thanks
(sqrt(cos(x))*cos(999999999999999999999999999999999999999999999999999 x)+sqrt(abs(x))-0.7)*(4-x*x)^0.01, sqrt(9-x^2), -sqrt(9-x^2) from -4.5 to 4.5" Now this guy forgot to credit the original user who made this. Me. And some dude from 2011 named "Nguyen Vu Long". SO CREDIT US!
(sqrt(cos(x))*cos(999999999999999999999999999999999999999999999999999 x)+sqrt(abs(x))-0.7)*(4-x*x)^0.01, sqrt(9-x^2), -sqrt(9-x^2) from -4.5 to 4.5

Copy-paste it noobs.

.999999999~ 

Grrrrrrr you anger me....learn some maths! .9999 recurring IS equal to 1! Hell, I'll even prove it for you if you like -
We all know that 1/3 (a third) can be written decimally as 0.333333 recurring (i.e. the 3s go on forever). It is also obvious that by multiplying a third by three, we get three thirds (3/3) , which is equal to one.
-
If we look at this same process decimally, take the number 0.33333 recurring and multiply it by 3, and you will see that each 3 in the sequence gets turned into a 9. This gives us .99999 recurring, which, since it is the same as 3/3, is also equal to 1, as explained in the previous paragraph.
-
The reason for this is that as you add more 9s onto the number 0.9 (after the decimal point), it gets closer and closer to 1. Since there are an infinite number of 9s after the point in 0.99999 recurring, the difference between this number and 1 must be infinitely small, and therefore cannot be any greater than 0.
QED.
.999999999~ (recurring) is equal to one because it is .333333~ (1/3) multiplied by 3.
.999999999~ by katzell September 25, 2005
More from Urban Dictionary

trucker's tan 

A sunburn or suntan focused on the left arm. It is caused by the left side of the body being the only half that gets exposed to sunlight while driving. Presumably, it would be located on the right side of the body in countries where they drive on the left side of the road.
I had a trucker's tan after driving for 10 straight hours on a sunny day.
Word of the Day on October 5, 2026
The phenomenon where adults salivate at children's toys
Every time I walk into the toy aisle, I catch myself kidulting over the latest action figures and LEGO sets!
kidulting by Emotional Cruiser October 12, 2025
Word of the Day on October 4, 2026
British slang for a scientist or technical expert, esp . when the speaker is not certain of the expert’s specific field of study. Not necessarily derogatory, but typically used by persons without a technical background. In the US, the equivalent would be “egghead”, “squint”, or “geek.”

Origin of the word is unknown. Started sometime in World War 2. Given the typical evolution of British slang, could easily have started because what these experts did was confusing or “baffling” to the common person.
According to the boffins downstairs, the murderer used a serrated blade.
Boffin by Agnon February 11, 2023
Word of the Day on October 3, 2026

Pee Calculus

When you have to pee in a movie but don’t want to miss anything, and must do the following mental equation: will the amount I have to pee cause enough discomfort to diminish my attention capacity for the remainder of the movie to an extent which is greater than the amount of the movie I would miss by making a mad dash to the restroom.
I saw Satantango last night, wonderful film but by the 5th hour I had to start doing pee calculus.
Pee Calculus by anorlondo October 1, 2026
Word of the Day on October 2, 2026
Literally "dirty" pronounced with a West Indian accent. Can also have a positive connotation, for example Sean Paul's album title "Dutty Rock".
"The girl is pretty but she corrupt and dutty!"

or, in a positive usage:

"Booya! That freestyle was dutty!"
Dutty by J Hall April 3, 2003
Word of the Day on October 1, 2026
korean word for madam, older woman
Ajumma wait a moment
Ajumma by aintnotinbutnice July 5, 2009
Word of the Day on September 30, 2026
Load more