阴 + Noun
The adjective 阴 (yīn) means "gloomy," "overcast," or "dark" and is used to describe weather, moods, or environments that lack brightness. It can also carry a metaphorical sense of gloominess or melancholy in literary contexts.
今天天气阴沉沉的,可能要下雨。
Jīntiān tiānqì yīnchénchén de, kěnéng yào xià yǔ.
The weather is gloomy today — it might rain.
连着好几天都是阴天,心情也不太好。
Lián zhe hǎo jǐ tiān dōu shì yīntiān, xīnqíng yě bú tài hǎo.
It's been overcast for several days in a row, and my mood isn't great either.
他的脸色很阴,看起来不高兴。
Tā de liǎnsè hěn yīn, kàn qǐlái bù gāoxìng.
His expression was dark — he didn't look happy.