A lobe is a roundish projection or subdivision of an organ of the body. Prefrontal lobes are situated at the front or forepart of the brain. A lobotomy is the surgical operation of cutting into a lobe such as that of the brain or the lung.

A prefrontal lobotomy is a psychiatric operation carried out by boring holes into the skull, entering the brain and severing the nerve pathways in the two frontal lobes, resulting in the patient becoming an emotional vegetable.