unwind
If you unwind something that is wrapped around an object, you unfasten it, and if it unwinds, it becomes unfastened.
解开，打开，松开(卷绕之物)
to unwind a ball of string
解开一团绳
He unwound his scarf from his neck.
他从脖子上解下围巾。
The bandage gradually unwound and fell off.
绷带逐渐松开脱落了。