Mayday /ˈmeɪˌdeɪ/

• 1. 

  N-COUNT 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. (飞机或船遇险发出的)无线电呼救信号

  例：

  He raced to pick up the life jackets while his stepmother sent out a Mayday call.

  他的继母发出无线电求救信号，他飞跑着去拿救生衣。