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When someone doesn't look at another's point of view.
I think you should apologise to me (even though I've deeply hurt you).
by Peter Smith September 15, 2003
Doing whatever it takes to make you happy and for some people, at least they're being who they are and not the stereotype of who they're supposed to be. Your inner child. Most people believe that age defines who you are and if you don't "act your age", you're immature. "Mature" people seem to be very depressed and settle for everything even if they don't want it.
Stuck up bitch: Why is that girl coloring in a spongebob coloring book? She's so immature.

Other person: At least she's doing what makes her happy, bitch.
by hofosho23 December 01, 2010
Immature is a person, usually 8-15 year's old, (and mostly male) who think sexual and inappropriate things are funny.
This drives me totally crazy, when your the only kid of you age that is way more mature then everybody else areound you (like me)
They call everything they don't like gay, or retarded, and anybody smarter than them a nerd, because they are to incapable of realizing that they are stupid, and (not to be hypocritical) retarded...
-Immature person- You got high honor roll in school? Hahahha! Your such a gay nerd!

-Civilized person- Your immaturity is making yourself look bad...Not me
by TheJazzKidOfTheSchool666 June 22, 2009
People who are annoying, don't know what they are talking about, and sometimes bitch way to much.
Look up Nu-Metal and you'll find many examples of the bitching part of immaturity.
by Drummer November 11, 2004
What people who post definitions to this site are best at.
Bob: Hey, did you see that definition on Urban Dictionary?
Frank: Yeah, it was immature at it's best. o_o
by TheOrlyGuyLol January 24, 2010
1. So many teenagers in this day and age who take the time to write immature definitions about s*xual related content, draw men's private parts everywhere they go, think of an inappropriate comment or get an inappropriate meaning from harmless statements by more mature people.

This adjective also describes most teenage boys in general, but I do know a few boys who do not make s*xual innuendos every other sentence.

2. People who think everything they can't do, they don't like, or disapprove of is 'gay'.

3. 'men' who think that women live to serve them.
Mature person 1: hey dude! Want to go---
Immature person 2: get some? Haha alright dude let's go!
Mature person 1: I was gonna say go get some coffee...

Immature person: dude, golf is so gay!

Mature person: just bc u can't do it doesn't mean it's gay.
by Ilovemydoggie23 December 20, 2011
In a generic age-irrelevant view of the concept: someone who wouldn't or can't get himself to do what they know is the right thing to do.
Someone who likes someone else but wouldn't act upon it; simply cause they are too immature to do what normal people would do.
by s-bandt November 05, 2011