mal del coco

1.
SpainLatin AmericaGeneral Spanishinformalpejorative
- A colloquial expression meaning to be crazy, mentally unbalanced, or irrational.
- Used to describe someone acting foolishly or as if they are not in full possession of their mental faculties.

Examples:

ES: A veces actúa como si estuviera mal del coco.
EN: Sometimes he acts like there's something wrong with his bean.
ES: ¿Estás mal del coco?
EN: Are you ill, old man?
ES: Está mal del coco.
EN: Yeah! Alright!
ES: Esa chavala, Teena, debe de estar mal del coco.
EN: This Teena chick seems pretty messed up.
ES: Este tipo está muy mal del coco.
EN: There's something seriously wrong with this guy.
ES: "No comas mucho de una sentada "o acabarás mal del coco".
EN: "You shouldn't have too much in one sitting or you'll go coco-nuts!"