π Elephant
"Elephant in the room"
Meaning
A big problem that everyone knows about but no one wants to discuss.
About the elephant
Elephants are large, hard to overlook, and reputed to have long memories, which shapes idioms about obvious problems and lasting recall.
Example sentence
The family meeting was polite until my sister finally named the elephant in the room: nobody had paid the electricity bill.
Test yourself
Which idiom means...
A big problem that everyone knows about but no one wants to discuss.