Surgery on any part of the nervous system, especially the brain; neurosurgery.(noun)
Something that is overly complex, detailed or confusing.(noun)
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Use "brain surgery" in a sentence
"In the last five days, Berezhnaya had suffered through brain surgery in a foreign hospital, the loss of her speech and the use of her entire right side, and the excruciating visits of Oleg Shlyakhov."