Mayday is one of several emergency- and distress-related code words from the French language used internationally as a distress signal.
- Mayday (m'aidez help me!) means that someone is in danger of death and needs immediate assistance.
- Pan (panne a breakdown) indicates trouble, but not mortal danger, such as a man overboard not being attacked by sharks. It is usually transmitted as Pan Pan and repeated three times. The suffix medico is added to indicate a medical problem (Pan Pan medico, repeated three times).
- Securitay (sécurité) indicates a message about safety, such as an approaching thunderstorm.
- Seelonce (silence) means that no one else may talk on the channel.
- Seelonce feenee (silence finie silence finished) means that others may now use the channel. The word prudonce (prudence caution) can also be used to allow restricted working to resume on that channel.
See also: call for help, SOS, distress signal