A fork of Rural Dictionary
a person who is a total genius. These people have GPAs of 5.1. Even though there is a lack of koo-i-ness in people, they totally own any other random last names. Comes with a huge abnormally large head. Common sense not included.
Wow did you see how that smart guy walked into a wall and then crushed it with his abnormally large head, must be a koo.