gaga
adjective
[ ˈɡɑːɡɑː ]
• no longer in possession of all one's mental faculties, especially on account of old age.
• "I want to write my memoirs before I go too gaga"
Origin:
early 20th century: from French, ‘senile, a senile person’, reduplication based on gâteux, variant of gâteur, hospital slang in the sense ‘bed-wetter’.
