It is the most meaningful “acronym” in the English language, despite meaning nothing. It does not stand for Save Our Souls, Stop Other Signals, Survivors On Ship, Sure Of Sinking, Send Out Succour, Save Our Sailors/Ship/Skins or any other such variant. It certainly does not stand, as one theory claims, for Spasiti Ot Smerti (the Russian for “save from death”).

SOS is simply the shortest, simplest three-letter arrangement in Morse code: three dots, three dashes and three more dots. The signal was deliberately chosen for its meaninglessness since it had to be universally recognised and not subject to language variations.

Like everything to do with maritime regulation, distress signalling was subject to intense international rivalry – while the British thought it sounded like a German derivation and the French would never accept something in English, the Italians and Americans had their own variations. But SOS was ideal, being short, symmetrical, memorable, inoffensive and without meaning in any language (except Greek: sos, by chance, is the inner stem of the verb “to save”.)

Despite (or perhaps because) it does not stand for anything in particular, SOS has become deeply embedded in our culture as a distinct word, complete with its own mythology and romance.

Times Archive, 1912: The Titanic Inquiry

Mr Marconi explained the rules under which wireless operators in steamers work, especially as regards distress signals

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In the long history of modern rescue SOS has been spelled out on beaches with rocks, flashed with a torch and stamped into snow. It has also been deployed to protect many things besides ships – the Sumatran Orangutan Society, Support Our Soldiers, Sustainable Open Space and so on – but it has also become the accepted distress signal for a broken heart.

Abba sang about it (“So when you’re near me, darling can’t you hear me, SOS.”), as did the Police in Message in a Bottle (“I’ll send an SOS to the world.”). Rihanna continued this rich tradition with her 2006 hit, SOS (Rescue Me), which begins: “Lalala lalala la la lala la Ohhh, You know . . . I never felt like this before.”

After a century, SOS has come full circle: it started off as completely meaningless and, in some circumstances, it still is.

In the Times Archive: on July 2, 1909 wireless telegraphy saved the Cunard liner Slavonia

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