Diencephalic syndrome (DS) is a rare condition characterized by profound emaciation and failure to thrive (with normal caloric intake and normal linear growth), hyperalertness, hyperkinesia and euphoria, in the presence of hypothalamic tumors.

An abnormal configuration of the lower lip such that it is turned outward i.e., everted, with the Inner aspect of the lower lip vermilion (normally opposing the teeth) being visible in a frontal view.