Someone who is somewhere in their late teens through early twenties, when they know everything and are absurdly idealistic.
by alm4400 December 26, 2010
The second decade of the 21st Century from 2010 to 2020 in between the Aughts (or The Aughties) & The Twenties. It's a portmanteau of the words tween, teen, and twenties.
Lady Gaga's career launched in the first decade of the new millennium, but will her popularity & influence on music prolong throughout the Tweenties?
by johnnydiva January 20, 2011