What Does COS Mean?

COS means "Because." The abbreviation COS is a short form of the conjunction "because." It can also be written as COZ.

COS can also refer to:
  • Church of Scientology. The Church of Scientology was formed in the US in 1953 by L. Rob Hubbard, whose studies first began in 1923. Tom Cruise and John Travolta are two high-profile celebrities associated with the religion.
  • Chief of Staff. A Chief of Staff is an executive (used in the military as well as business) whose role is to coordinate the activities of the other seniors and departments.

Image for COS

When I write COS, I mean this: meaning of COS COS is short for "Because."

Summary of Key Points

"Because" is the most common definition for COS on Snapchat, WhatsApp, Facebook, Twitter, Instagram, and TikTok.
Type:Slang Word (Jargon)
1: Easy to guess
Typical Users:
Adults and Teenagers


Examples of COS in Sentences

Here are examples of COS being used in conversations:
  • Millie: Why do I have to eat that?
  • Ian: COS it's good for you.
  • Andrew: Apparently, I snore so loudly that it scares everyone in the car I'm driving.
  • Ali: Is that supposed to be funny, COS it's not!

An Academic Look at COS

COS is a shortened version of because and is therefore a contraction. Contractions tend to be formed in one of three ways:
  • Using letters from the start of the word (e.g., AMP from amplifier).
  • Using letters from the start and end of the word (e.g., Dr from Doctor).
  • Using an apostrophe to replace a letter or letters (e.g., can't from cannot).
For reasons of brevity, contractions are rarely followed by periods/full stops and apostrophes are routinely omitted in text speak and on social-media platforms.

What Did We Say before Texting and Social Media?

Before the digital era, we would have written "because" or possible "'cause" instead of COS.

Example of COS Used in a Text


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