Which term describes someone showing a brooding ill humor?

The term that describes someone showing a brooding ill humor is "Saturnine." This word is derived from the Roman god Saturn, who was associated with melancholy and gloominess. When used to describe a person's demeanor, it implies a heavy, morose, or sulky personality, often reflecting a sense of seriousness or sadness that tends to overshadow their mood. Therefore, it effectively captures the essence of someone who is not only dark in temperament but also possibly inclined to be reflective or cynical.

In contrast, the other terms convey different meanings. "Sanguine" refers to a cheerful and optimistic disposition, which is the opposite of brooding ill humor. "Recumbent" describes a position of lying down or resting, having no relation to mood or temperament. "Seine" is a type of fishing net and is unrelated to personal demeanor. Understanding these distinctions highlights why "Saturnine" is the appropriate choice for describing someone with a brooding and ill-humored attitude.