Answer:
1.make or become dark or darker.
"the sky was darkening rapidly
2.make or become gloomy, angry, or unhappy.
"his mood darkened"
• (of someone's eyes or expression) show anger or another strong negative emotion.
"his face darkened and he lunged away"
•(of anger or another strong negative emotion) show in (someone's eyes or expression).
"misery darkened her gaze"
