Cookl can be used in many forms. It has originated in the use of internet chat as a spelling error of cool. This word has evolved to become used more widely though, It can be used to explain the level of acceptance of something, or even to explain how angry one can be, amoungst many other things. See examples below.
How are you feeling?
I am so cookled right now (expression of frustration)
I am going cookl (crazy)
You are such a cookl (playfully moron)