Story time. My family and I moved to Egypt about a year ago after I resigned from my cushy government job in DC. On a recent trip to the zoo, my wife discovered that her word for lioness is not acceptable for use in polite company in Egypt. In Egypt, the standard Arabic word for lioness (labwa) means whore or slut. So instead of using the standard Arabic word, Egyptians say "marat al-asad," or "the lion's wife." I already knew about that and my wife asked me how I knew. I had learned more than a few inappropriate words from Arab friends. But's that's not the interesting part.
Rewind ten years and I was a new government employee working on my beginner-level Arabic with a tutor. This tutor was a Syrian lady who eventually was reassigned after a few awkwardly impassioned outbursts in defense of Syrian dictator Bashar al-Assad in front of her students. And now I was sitting with her, discussing animals.
What I haven't told you is that "marat al-asad" or "the lion's wife," depending on context, could mean "Al-Assad's wife," referring to Asma al-Assad, first lady of Syria. My tutor apparently didn't know about the Egyptian slang. And redfaced, trying to control her rage, my tutor sat and listened to me trying to explain in my beginner's Arabic why I was using the vocabulary I was using, saying in so many ways what sounded to her like "Al-Assad's wife is a whore."