21

1. The number between 20 and 22.

2. The age that you are legally allowed to drink and go into bars and nightclubs.

3. The sum of 9+10, according to a dumbass overplayed video on a popular mobile app called Vine, which lets people create quick 5-7 second videos and post them. The video goes like this.

Teenager: you stupid
5 year old boy: no I'm not.
Teenager: what's 9+10?

5 year old boy: ... 21?

Teenager: you stupid.

The original video has been made fun of all over the internet. People do remakes of it, have added the little boy saying "21" into popular videos, and have created songs about it, usually taking the beat of Bobby Shmurda's "Hot Nigga". It was on the news that the kid ran away from home, because he was sick of being made fun of.

Go up to anybody and ask them what's 9+10 and they will answer 21.

21 by delilahmonique December 7, 2014

21

someone who takes 21 dollars as a payment for sexual favors

Courtney is such a 21.

21 by Deenz July 29, 2008

21

21 can be used to insult people by using the fact that they only have 21 pairs of chromosomes. (the normal amount is 23 and any difference from 23 will make them deformed)

You know Kevin? yeah, hes so 21

21 by Panik1209 March 2, 2011

21

The sum of the numbers 9 and 10, this is also the legal drinking age for the United States of America. At the age of 21, you can drink and drive in the U.S., although this isn't recommended in the U.S. as it is highly illegal. This number is a great number to use on your fake I.D. for the age you are.

"Wyatt, what is 9+10?" "21" "Thanks pal"

21 by Pedro K. Hasseem December 5, 2017

21

The age of which an American has reached their true potential

I just had my 21st birthday and now I’m gonna die of alcohol poisoning!

21 by Licc December 27, 2020

21

The best number, and the only number funnier than 24 OR 25.

Person 1:"21"
Person 2 looks at Person 1, proceeds to punch Person 1.
Person 1:"Hey, hey, what's 9+10?"

21 by Dickosaurus May 20, 2016

21

A general noun that can mean anything

Yo, let me see that 21.
Yo, that 21 ain't done yet.
Yo, I been seen that 21.

21 by Moses jumppiece October 9, 2006