A rounded, projecting part of an organ, especially the ear or the brain; any rounded division of something.
From Greek 'lobos' (lobe, pod), possibly related to 'lepis' (scale). The word entered English in the 1600s and was applied anatomically to the brain, ear, and lungs.
Your brain has a 'frontal lobe' and 'temporal lobe,' and your ear has a 'lobe'—all using the same ancient Greek word for something rounded and pouchy, showing how Greeks must have noticed this same bulging shape in different parts of the body.
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