SOS
Abbreviation with 3 meanings
| Stands for | International Morse code distress signal |
|---|---|
| Meanings | 3 |
| Categories | Writing & Everyday, Government & Politics, Medical |
| Also written | s.o.s., SoS |
SOS has three meanings. The most common are International Morse code distress signal (everyday) and Secretary of State (political); it can also stand for Si opus sit (if necessary).
Meanings of SOS at a glance
| # | SOS stands for | Context |
|---|---|---|
| 1 | International Morse code distress signal | Writing & Everyday › Everyday |
| 2 | Secretary of State | Government & Politics › Political |
| 3 | Si opus sit (if necessary) | Medical › Prescription |
1. International Morse code distress signal
Writing & Everyday · Everyday Abbreviations
Serves as the internationally recognized distress signal, sent in Morse code as three dots, three dashes and three dots, and used figuratively for any urgent call for help.
Example: Stranded hikers stamped SOS in the snow, and a rescue helicopter spotted it the next morning.
SOS was adopted by the 1906 International Radiotelegraph Convention in Berlin and took effect in 1908 because its Morse pattern is easy to send and recognize; the letters were chosen for that pattern, not for words. Popular expansions such as "Save Our Souls" or "Save Our Ship" are backronyms. The Titanic sent both SOS and the older CQD in 1912. Voice radio uses "Mayday."
2. Secretary of State (SoS)
Government & Politics · Political Abbreviations · also used in transportation
Title of two very different US offices: the federal cabinet member who leads the State Department and conducts foreign policy, and the state-level official who in most states runs elections, registers businesses and keeps official records.
Example: Check the SoS website to confirm that your voter registration is active.
The federal Secretary of State is fourth in the presidential line of succession. Forty-seven states have a secretary of state; in Alaska, Hawaii and Utah, the lieutenant governor handles comparable election duties. The capitalized SOS is the Morse code distress signal and is unrelated.
3. Si opus sit (if necessary) (s.o.s.)
Medical · Prescription Abbreviations
Older Latin instruction meaning a dose may be given once if needed, for example for pain or sleeplessness. It is still seen in prescriptions from India, parts of Europe and Latin America, but has been replaced by PRN in North America.
Example: Paracetamol 500 mg s.o.s. for fever above 38.5 C.
Latin "si opus sit", "if there is need". Traditionally s.o.s. meant one dose only, unlike PRN, which allows repeated doses. It has nothing to do with the Morse distress signal SOS, which is not an abbreviation of anything.
Related abbreviations
More everyday abbreviations
- R&R – Rest and relaxation
- rec'd – Received
- Reg. – Regular (price)
- soc. – Society
- std. – Standard
- temp. – Temperature
- TLC – Tender loving care
- univ. – University
See all 82 everyday abbreviations →
More political abbreviations
- SCOTUS – Supreme Court of the United States
- Sen. – Senator
- SFRC – Senate Foreign Relations Committee
- SG – Solicitor General
- SOTU – State of the Union
- SSCI – Senate Select Committee on Intelligence
- STV – Single transferable vote
- Super PAC – Independent expenditure-only political committee
See all 91 political abbreviations →
This entry is for general education and is not medical advice. Abbreviation use varies between institutions; always confirm in context.