one end of a rope tied to form a circle that can be tightened round something such as a person's neck to hang (= kill) them

They put him on the back of a horse and looped a noose around his neck. 他们把他放在马背上，并用绳索套住他的脖子。

a serious problem or limit

The noose of poverty was tightening (= becoming more serious) daily. 贫困问题日益加剧。