lobe

1. Any projection or division, especially one of a somewhat rounded form. [from 19th c.]Examples: "A lobe of lava was crawling down the side of the volcano."; "He then broke the kola nut and threw one of the lobes on the ground for the ancestors."

2. (anatomy) A clear division of an organ that can be determined at the gross anatomy level, especially one of the parts of the brain, liver or lung. [from 16th c.]Examples: "The yawning gap in neuroscientists’ understanding of their topic is in the intermediate scale of the brain’s anatomy. Science has a passable knowledge of how individual nerve cells, known as neurons, work. It also knows which visible lobes and ganglia of the brain do what. But how the neurons are organised in these lobes and ganglia remains obscure."

3. (figure skating) A semicircular pattern left on the ice as the skater travels across it. [from 20th c.]