SPLEENS

In vertebrates, including humans, a ductless vascular gland, located in the left upper abdomen near the stomach, which destroys old red blood cells, removes debris from the bloodstream, acts as a reservoir of blood, and produces lymphocytes.

(except in the set phrase "to vent one's spleen") A bad mood; spitefulness.

A sudden motion or action; a fit; a freak; a whim.