The term 'Lung Division' refers to the anatomical structure of the lungs, which are divided into lobes. The four-letter word for this is 'LOBE'. The lungs are divided into two lobes on the right side and two lobes on the left side, with each LOBE containing a bronchus and a bronchiole. The lobes are separated by fissures, which are deep grooves that allow air to pass between them. The lobes are further divided into smaller segments, which are connected to the bronchi and bronchioles. The lobes are responsible for the exchange of oxygen and carbon dioxide in the body.