N-COUNT
(飞机或船只遇险时发出的)无线电呼救信号
If someone in a plane or ship sends out a Mayday or a Mayday message, they send out a radio message calling for help because they are in serious difficulty.
例句
He raced to pick up the lifejackets while his stepmother sent out a Mayday call.
他的继母发出无线电求救信号的时候,他飞跑着去拿救生衣。