SOS

Chosen because its morse code sequence (...---...) was easy to remember and recognize even through interference. Many mnemonics and backronyms were later formed from the sequence.

SOS

1. (radio slang) emergency, mayday, distress

The code SOS is normally only used in text transmission; for voice communication, mayday is used. The sequence is normally transmitted run together without any letter spacing in between, so it is technically a single unique code rather than a series of three letters.

• mayday

• pan-pan

SOS

1. Somali shilling

This is a currency code used in the ISO 4217 standard.

• (UK) IPA^(key): /ˈɛs.əʊˌɛs/

From the letters represented by the signal, chosen as a sequence that is easy to recall and transmit (· · · — — — · · ·); it is not, as is commonly believed, an abbreviation for "save our souls", "save our ship" or any other phrase.

SOS (plural SOS's or SOSes)

1. The conventional Morse code call made by a ship in distress.

   The keel has been scuppered! Send out an SOS.

• mayday
• pan-pan

SOS

1. Initialism of Secretary of State.
2. Initialism of special order sale.

SOS (uncountable)

1. (games) A children's game in which players take turns to place S's and O's on a grid, collecting points by creating an "SOS" sequence.

• tic tac toe

• 'oss, OSS, OSs, SSO, oss

Borrowed from English SOS.

• (Tokyo) エスオ​ーエス [èsúóꜜòèsù] (Nakadaka – [3])[1]
• (Tokyo) エスオーエ​ス [èsúóóéꜜsù] (Nakadaka – [5])[1]
• IPA^(key): [e̞sɨᵝo̞ːe̞sɨᵝ]

SOS (katakana エスオーエス, rōmaji esuōesu)

1. SOS (conventional Morse code call made by a ship in distress)
2. (by extension) the state of being sought an emergency rescue

   火 (か)星 (せい)からのSOS (エスオーエス)

   kasei kara no esuōesu

   an SOS from Mars

3. silicon on sapphire