gaga /ˈɡɑːɡɑː 
, ˈɡaɡə / ▸ adjective informal 1 very enthusiastic and excited about someone or something: moviegoers went gaga over Harry Potter
we are all gaga over Diane's gorgeous designs
he comes across all quiet and shy but the women go gaga for him.
2 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
how many raves can you go to without ending up completely 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’.
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