Saturnine
Etymology
From medieval astrology, "of Saturn," the planet believed to shape those born under it. Saturn was the slowest, most distant known planet, associated with cold, heaviness, and a leaden gloom, so a saturnine person was thought to inherit that dark, sluggish temperament. When the astrology faded, the melancholic character it described stayed attached to the word.
adjective · /SAT-ur-nine/
Gloomy, cold, and slow to warm; darkly and taciturnly melancholic in temperament.
What it names
The heavy, shadowed disposition of a person who seems perpetually withdrawn into a somber inner weather.
Example
His saturnine silence at dinner made even cheerful guests lower their voices.
Related idea
Melancholy is a mood of pensive sadness; saturnine describes a whole cold, brooding cast of temperament, not just a passing state of feeling.