Definition & Meaning of "splenetic"in English

What is the origin of the term "splenetic" and how is it used?

"Splenetic" is a term used to describe a person who is habitually irritable, spiteful, or angry. It comes from the Latin spleneticus and the Greek splēn, meaning "spleen," because the spleen was historically believed to be the source of anger and ill temper in the body. The word has been used in English since at least the 16th century to describe a bad-tempered disposition. It is mildly derogatory, mostly appearing in literary, formal, or humorous contexts rather than as a harsh insult.