look up any word, like jamflex:
 
8.
the reason for so much evil and stupidity on this earth. everything that is wrong on earth is caused by adults and still children gotta respect them.
rick-i have become an adult now

jack-oh welcome to moronhood
by martianthemarvin June 09, 2011
 
9.
noun:1)An individual who is old enough to take complete responsibility for all of his/her actions. Often described by the goverment as a person who has reached a certain age (e.g. a person 18 years old or more). Adjective: 2)Pertaining to adults. 3)Describing sexually suggestive material.
1) Only adults are allowed to buy tobacco here.
2) Little Mindy asked why some things were too adult for her to understand.
3) Strip clubs offer adult entertainment.
by Mintaddict February 08, 2004
 
10.
Someone to doesn't deserve the privilege to be called an "adult."
Fred steals, robs people, kills animals, and jay walks. He's not an adult, he is a dult.
by Boston Travis April 29, 2008
 
11.
plural form of adult.
there's on adult here, and three adults over there.
by grah October 23, 2007
 
12.
A soul broken by society; someone who has lost faith in people.
Little Timmy: I can't wait to grow up!

Adult Timmy: Why didn't I appreciate my childhood more!
by TheOneInTheSun October 19, 2011
 
13.
1. The stage after adolescence.

2. Legally, someone who is (usually, depending in what country you live) 18+.

Now, there is a difference between legally and biologically.
At 18, in most country, you are legally an adult.
But, since most people continue to grow in some way at 18, they can't be considered adults physically.

Even if most people at 18 are "physically" teenagers(they continue to grow), you're still considered an adult, but it's not rare that people who are 18-19 are called "teens" (probably because of the number, eighTEEN, nineTEEN)

It is confusing, since at 18-19, you're both an adult(legal) and teenager(physically).

Because of that confusion, people of that age (18-19) are generally called "young adult".
Marc is 18, he is an adult.
by blackdeath1289 January 27, 2007
 
14.
Independent, responsible person..preferably over the age of 25.
by jen August 22, 2003