distress signal

English Thesaurus

1. an internationally recognized signal sent out by a ship or plane indicating that help is needed (noun.communication)

hypernym	:	sign, signal, signaling,
definition	:	any nonverbal action or gesture that encodes a message (noun.communication)

hyponym	:	sos,
definition	:	an internationally recognized distress signal in radio code (noun.communication)

hyponym	:	mayday,
definition	:	an internationally recognized distress signal via radiotelephone (from the French m'aider) (noun.communication)