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A) A nice ass way of saying it gets most of the job done
B) A term used by companies so that they don't get sued when their product doesn't work 100%
C) not quite enough; almost
Dude, it says on the label that this new orange mango-tango blueberry-raspberry slam-a-bam anti-bacterial soap kills 99.9% of germs.
5 hours later...
I have AIDS
99.9% by Chernasex April 4, 2006
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something big retailers use when their product(s) aren't 100% because of possible side-effects or holes in the design
and i would not be doing my job if i did not ask what the other 0.1% is for. 99.9% just ain't effective
99.9% by your best idiot April 6, 2010
When a psychic is almost 100% full, they're about to blow from emotions.
"Mob is at 99.9%!! REIGEN!!!"
99.9% by thismyhandle June 5, 2026
Almost one hundred percent positive; however still leaving slight room for error.
Guy: You were pretty drunk last night. Did you eat the last frozen pizza?

Roommate: No.

Guy: You sure?

Roommate: (Shrugs) 99.9 anyway
99.9 by Ventghal February 27, 2008
An expression of joy, happiness and tranquility.Pronounced nintey nine nine it's used by Toyota Prius owners when their MPG indicators max out at 99.9 miles per gallon.
How are you doing today? I just got promoted and my asshole manager got fired so I'm 99/9.
99/9 by vivian darkbloom May 25, 2007

99.9...% Sure 

Sometimes people, when expressing how certain they are of something, say they are 99% sure of something. Oftentimes, however, they choose to add validity to their statement by adding 9s behind the decimal place, thinking that will prove their words to be truth beyond belief. We can create a scale of how sure a person actually is based upon the numbers of 9s behind the decimal in their percentage:

99.9% sure: 99.9% is absolutely rock-solid; a person who says they are 99.9% sure of something is presenting insight with undoubtable knowledge of the topic. This information can be counted on.

99.99% sure: 99.99% is still measurably accurate. Usually, 99.99% is reserved for situations in which there still remains room for unexpected events. This information can still be counted on, but watch out.

99.999% sure: 99.999% represents the beginning of a slippery slope of doubt. 99.999% generally is used for opinions or statements that cannot be backed with empirical evidence. Most people who frequently express political beliefs will say they are 99.999% sure of something. Be careful before believing someone who is 99.999% of something.

99.9999% sure: At this point, we cannot be completely sure of how positive someone is of something. If a person says they are 99.9999% sure of something, it is basically a 50/50 situation.

99.99999% sure: If a person says they are 99.99999% sure of something, they genuinely have no fucking clue what they are talking about.
99.9...% Sure:

Connor: I am 99.9% sure that the sun will rise tomorrow.

Daniel: I am 99.99% sure that the next Battlefield game will be kickass.

Evan: I am 99.999% sure that Dirk is a homosexual.

Dirk: I am 99.9999% sure that Evan has been raped in the shower.

Johnny: I am 99.99999% positive that Socialism will prevail.

Rebecca: I am 99.999999% certain that I was a cow yesterday and will be again tomorrow.

I’m better than 99.9% of all the other UrbanDictionary users out there

I’m better than 99.9% of all the other UrbanDictionary users out there.
More from Urban Dictionary
A girl who does ballet and only talks about ballet. Her schedule is filled with dance classes which does not allow her to do any other activity.
"Hey, do you know that girl Sally?"

"Yeah, she's kind of annoying. All she ever talks about it ballet."

"Wow, what a Bunhead."

"Hey Sally, you want to hang out this weekend?"
"I can't, I have dance."
"You're such a Bunhead."

"Yeah... I know."
Bunhead by Jen00 October 24, 2014
Word of the Day on October 6, 2026

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
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