What is Thrin?
1.
Young women, usually overweight, that are so egocetnric and self-absorbed that they make up cute little words to describe themselves and their so-called "friendship".
Those three fatties we met from Wisconsin seemed cool at first, but then they turned out to be total thrins.
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2.
A group of three friends who are very close, like sisters. Like twins, only three.
Maddy, Rikki, and Miranda were better known as "The Thrins" at school.
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Random Words:
1. 
A way to tell someone that something's wrong, even if they don't know about it. Taken from season 5, episode 2 of Gilmore Girl..