Suburban white bread 5th and 6th graders, who think they know everything, and do not want to be referred to as "children".
-They have no real music tastes of their own, and just listen to what's on the weekly top 40 chart, because they think it makes them seem "cool".

- Frequently shop at stores like "Hollister" and "Aeropostal" with the 200 dollars their parents give them for clothing that they "need". These tweenies think it's cool to shop in the "teenager" stores, and buy all the size 0s and Xsmalls.

-They often have high priced electronic accessorys that no 10 year olds needs. Such as an "iPhone".

-Most have either Middle aged mothers who still think they're 20, or overweight, dumpy moms who try to live their life through their child.

-Warning! they will get extremely offended if you in any way imply that they are still a child.
Normal 10 year old- "Wanna go play with dolls?"
Tweenster 10 year old- "WTF no, dolls are for 9 year olds, stupid."
by PseudonymixYah March 14, 2009
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a person in their twenties, a person between twenty and twenty-nine years of age, the years of a century of a person's life.
"he's in his late twenties"
she’s a tweenster, in her early twenties and doomed to be another cute empty hooker on Craigslist
by PearlmanNB October 25, 2017
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