What does the expression "Elephant in the room" mean?

Elephant in the Room: Obvious Issue Ignored

When people refer to the "elephant in the room," they mean there's a big, obvious issue or problem that everyone is aware of but no one wants to talk about. 

It's like having a large elephant in a small room that everyone sees but pretends not to notice. 

This phrase is often used to draw attention to uncomfortable topics that people are avoiding. 

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