SOS

¹ American  

1. the letters represented by the radio telegraphic signal ( – – – ) used, especially by ships in distress, as an internationally recognized call for help.

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noun

1. any call for help.

   We sent out an SOS for more typists.

verb (used without object)

1. to send an SOS.

SOS ² American  

abbreviation

Slang.

1. shit on a shingle (a euphemistic initialism used to avoid explicit vulgarity).

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s.o.s. ³ American  

abbreviation

1. (in prescriptions) if necessary.

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SOS British  

noun

1. an internationally recognized distress signal in which the letters SOS are repeatedly spelt out, as by radio-telegraphy: used esp by ships and aircraft

2. a message broadcast in an emergency for people otherwise unobtainable

3. informal a call for help

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Usage

What does SOS mean? The letter sequence SOS (pronounced S-O-S) is used in Morse code as a distress signal—a way to call for help during an emergency, such as on a ship.Morse code uses clicks and pauses, short and long sounds, or flashes of light to represent letters and numbers. S is represented by three short clicks or brief flashes of light, and O is represented by three long sounds or longer flashes of light (depicted with dashes).Morse code can be written out using dots to represent short clicks and dashes to represent long ones, resulting in a specific sequence for SOS (··· – – – ···) that was chosen since it would be easy to communicate with sounds over radio or with flashes of light.The signal became well-known enough that SOS came to be used as an informal term for any call for help or notification that there is an emergency, as in Send an SOS to the board letting them know that we’ll have to schedule an emergency meeting. When used this way, each letter is still pronounced individually (S-O-S). The plural of SOS can be written as SOSs or SOS’s. SOS can also be used as a verb meaning to send such an SOS.Example: I have my phone set up to automatically send an SOS to certain contacts if I ever dial 9-1-1.

Etymology

Origin of SOS¹

First recorded in 1905–10; from the Morse code alphabet, in which three dots (or short clicks) represents the letter S and three dashes (or long clicks) represents the letter O

Origin of s.o.s.³

From Latin sī opus sit

Example Sentences

Their company, Curbside SOS, was bought last month by roadside-assistance platform Honk Technologies, which is controlled by private-equity investor Frontenac, said Matt Maloney, co-founder of Grubhub and Curbside.

From The Wall Street Journal • Apr. 3, 2026

"It's a miracle they managed to send an SOS," Singh says, which was picked up by the Sri Lanka Maritime Rescue Coordination Centre in Colombo.

From BBC • Mar. 6, 2026

Smith answered an SOS call last week and flew to Sri Lanka after captain and regular opening batsman Mitchell Marsh was injured by a throw-down during batting practice in Colombo a week ago.

From Barron's • Feb. 16, 2026

The goal of SOS is to impose standards in the social media industry much like video game, music and television industries caters to independent rating systems that indicate the age appropriateness of content.

From Salon • Feb. 11, 2026

McCandless’s signature had been penned at the bottom of the SOS note, and the photos, when developed, included many self- portraits.

From "Into the Wild" by Jon Krakauer

Related Words

• admonition
• advice
• alarm
• alert
• caution
• example
• guidance
• hint
• indication
• information
• lesson
• notification
• prediction
• recommendation
• sign
• signal
• suggestion
• threat
• word