ring-off lamp话终指示灯;拆线指示灯
ring-off话终振铃
ring-off button拆线按钮
ring-off indicator空线指示器
ring-off signal话终信号
ring g off挂断电话
ring-off lamp in pair话终指示对灯
PHRASAL VERB（动词词组） When you ring off, you put down the receiver at the end of a telephone call. 挂断电话 [英国英语]
Don't ring off!
不要挂断电话！