LOBOTOMY definition : 1. a medical operation in which cuts are made in or near the front part of the brain, used in the…. Learn more. Lobotomy , also known as leucotomy, is a discredited form of neurosurgery that involves severing parts off the brain's prefrontal cortex. It was created in 1935 by António Egas Moniz, a Portuguese neurologist. Looking for online definition of lobotomy in the Medical Dictionary? lobotomy explanation free. What is lobotomy? Meaning of lobotomy medical term. What does lobotomy mean ? A lobotomy , also called a leucotomy, is a type of psychosurgery that was used to treat mental health conditions such as mood disorders and schizophrenia.