The name is a direct borrowing from the Greek word splen. The spleen is located in the upper left quadrant of the abdomen behind the stomach. Despite its location, it has nothing to do with digestion, but works in regulating blood components, particularly, culling out aging red blood cells. At one time this organ was thought to be the seat of emotions. Have you ever been really angry and “vented your spleen” at some one? And, in response, your listeners might have characterized you as “splenetic”.