The sky becomes dark at night, but a moonless night is darker because the moon isn’t offering any light. You might see cloudy weather before it rains. In overcast weather too, there are clouds covering the sun, but there is no rain. When it starts raining, the sky is still cloudy, but it is no longer overcast. You might want to describe a caliginous morning if it was still quite dark and misty outside, but be careful – this word is only used in the formal literature, which makes it awkward for day-to-day usage. How would you describe an indoor setting with little light? A basement might be pitch-dark before you turn on the lights, meaning that you can’t see anything in the almost-complete darkness. A room would be gloomy if it only has a small window and a single lamp for light, but it would be dingy if it were poorly lit while also being dull (and often dirty) in its furnishings. Clearly, using “dingy” provides more information in a single word, which is useful for effective communication. Let’s look at some more words to help you express exactly what you’re trying to say.