To break, ruin, or render something useless, or to describe something as ugly. When used regarding people, it means to physically beat someone up or to look exhausted and worn down. It is a vulgar term similar to fuck up or wreck. (In Mexican slang, many aggressive or strong expressions are derived from the word madre, meaning mother).
-My car is very madreado, I will have to get a tune-up. -If you keep bothering me I am going to madrear you. -What is wrong? You look very madreado. -Now that you painted your house it looks really madreada, that color is hideous.