In popular usage, “schizophrenic” (and the more slangy and now dated “schizoid”) indicates “split between two attitudes.” This drives people with training in psychiatry crazy. “Schizo-” does indeed mean “split,” but it is used here to mean “split off from reality.” Someone with a Jekyll-and-Hyde personality is suffering from “multiple personality disorder” (or, more recently “dissociative identity disorder”), not “schizophrenia.”
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