What does COS mean in a message?

Child over shoulder

COS is a warning meant to alert the recipient that a child is watching over their shoulder, so don't send anything inappropriate. It is similar to the POS acronym sometimes used by kids to warn friends that their parent is watching their device.

Parents may send COS when their kid is sitting in their lap and can see their phone when texting. Or, a sitter may send it when messaging a friend online, and a child is near them.

However, since COS is rather obscure, it may confuse the recipient more than actually be helpful. Therefore, unless the person you are sending it to is slang-savvy, you should probably just spell it out instead of using the acronym.


COS right now, so if I seem a little distracted, that's why.

When your child is watching you like a spy

Related Slang


Updated February 14, 2022

COS Definition by

This page explains what the acronym "COS" means. The definition, example, and related terms listed above have been written and compiled by the team.

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