When I was growing up, the rudest and most unacceptable word you could say was the f-word. 

That’s what we called it, too — the “f” word — and even using that initialism was dangerous. We didn’t call it the “f-bomb” back then. That would come later, when the word had acquired a certain raffish popularity. If we absolutely had to, if there was no way around it — something like, Mom, some kids were using the f-word at the park — you had to say it with as much aghast disapproval as you could muster at 7 years old.