Big no-no - Tradução em português

Hi Experts


Today in the morning I was listening to BBC Learning Podcast called 6 Minutes English and there was the expression 'a big no-no' in the context bellow:

"Yes, that is a big no-no for me, I really don't like that, it really breaks my concentration."

What does it mean?
According with BBC Learning English it means "something most people don't like".

So basically "a big no-no" is something that should not be done or should not have been done. It was a big error or bad manners.

I hope that helps.
Caio.