A female version of a gumby (Someone with little or no co-ordination or common sense and lacks any talent or potential to do anything but fuck everything up. - Scotty). Originally used to describe a particularly gumby Punjabi girl called Priya.
Priya we'll never get this spit roast going with you being such a gumbette!
One who is destined to live the rest of their days looking, sounding or acting like a 12 year old. Etymology: a portmanteau of permanent and tweenager
Nirusha, stop acting like such a goober
. You're 22 for God's sake, you'll end up a permatween at this rate.