Mook is a universal level word, the word can mean anything depending on the situation. The word can be used to congratulate, insult, greet, and etc. The definition was created by Timilehin Lamoriu, Mookasan (Mr. Mook), who took the insipration from the Japansese word "san" meaning "Mr/Mrs"
Good morning Mook (greeting)
You stupid Mook (insult)
I'm so proud of you Mook (congratulate)