The origins of SOS and Mayday
S.O.S became the worldwide standard distress signal (particularly in maritime use) on 1 July 1908, having first been adopted by the German government three years earlier. It has since entered the awareness of those who are unlikely ever to summon help at sea – appearing in contexts as varied as the title of songs by ABBA, Rihanna, and the Jonas Brothers, and the home renovation TV programme DIY SOS.
The origin of S.O.S.
Various theories have arisen regarding the origins of S.O.S., with suggestions that it is an initialism for save our ship, save our souls, or send out succour. Given its German origins, it would be surprising if S.O.S. stood for an English expression – and in fact these are all examples of folk etymology. S.O.S. doesn’t stand for anything but was chosen because it is easily transmitted in Morse (also known as Morse code), an alphabet named after its inventor Samuel Morse in which letters are represented by combinations of long and short light or sound signals. S.O.S. is transmitted as · · · – – – · · ·; that is, dot-dot-dot, dash-dash-dash, dot-dot-dot.
Within a decade of its standardization, the term S.O.S. was used outside of radio code signals, in the transferred sense of ‘an urgent message or appeal for help’, and has also been used as an abbreviation for various informal phrases beginning same old (same old stuff, same old story, etc.).
Mayday, an international radio distress signal used especially by ships and aircraft, has a more linguistic origin than the pragmatic approach of S.O.S. Although a connection to the month of May might seem likely, it is actually an anglicization of the French m’aidez or m’aider, meaning ‘help me’.
It is believed to have been chosen in 1923 by Frederick Stanley Mockford, a senior radio officer in London’s Croydon Airport. The earliest example in the Oxford English Dictionary (OED), according to current research, is from an article in the British newspaper The Times, which notes that Mayday is chosen in preference to S.O.S. “owing to the difficulty of distinguishing the letter ‘S’ by telephone”.