lobotomy lo·bot·o·my (lə-bŏt'ə-mē, lō-)
Incision into a lobe.
The division of one or more nerve tracts in a lobe of the cerebrum.
A surgical incision into one or more of the nerve masses in the front of the brain. A lobotomy may be performed for the relief of certain mental disorders, although it has been largely abandoned in favor of less radical treatments.
Note: Because people who have had a lobotomy often become quite passive after the operation, the term is often used to refer to someone who shows a lack of response or reaction: “She was so tired she just sat there as if she had been lobotomized.”