Alternative form of brainwave

Someone who does brain surgery. / (idiomatic) Someone very intelligent.

(obsolete) an impetuous, fiery person; a hothead

Alternative spelling of brain-dead

(medicine) An irreversible loss of brain function and cessation of brain activity.

(medicine, not comparable) Having an irreversible loss of brain function and cessation of brain activity. / (colloquial) Having no useful thoughts; stupid; ditzy.

(informal) The temporary inability to think properly, or to remember something

(pathology) Alternative spelling of brain fever

(pathology, dated) encephalitis or meningitis

A complex riddle or puzzle.