Definition of "gaga"

gaga¹

/ˈɡɑːɡɑː/

adjective
comparative more gaga, superlative most gaga
1. (informal) Mentally senile.
2. (informal) Crazy.
  Quotations
  Should he lose it once and for all, he and Kathleen would need lots of money. Also, he had said to me, you could be gaga in a tenured chair at Princeton, and would anybody notice?
  1975, Saul Bellow, Humboldt's Gift, Viking, page ??
3. (informal) Infatuated.

gaga²

/ˈɡɑːɡɑː/

noun
uncountable
1. Alternative form of ga-ga (“game resembling dodgeball”)