This incident is a very good example of cultural misunderstanding. I have many friends in the UK, and one thing that I've learned over the years is that British people in general have much more emotionally charged reactions to words like "retard" and "spazz" than American people in general.

Words like that are received as highly offensive profanities. People learn from the time they're very young children that the words are unacceptable in any context.

I've had incidents where I've used a word that I had no idea was rooted in mocking disabled people and had British friends gasp in sincere emotional shock.

When words become taboo, the equivalent of profanity, it's hard to use reasoning to argue for their use.

I've defended some of my usage to British friends, explaining that in America people generally don't perceive the words the same way Brits do. And while they can hear me and accept what I'm saying, they can't stop having a highly charged emotional reaction to the words.

The same works in reverse. Take the wore c*nt, which to my American years is absolutely taboo, perhaps the worst or one of the worst profanities in the English language. I have an emotionally charged reaction when I hear it, because that's how I've been conditioned.

Not so the British. In the UK that word is a mild profanity and while it isn't something you would typically say in a formal setting, it is not at all taboo. I've even heard MPs use the word while making speeches in Parliament, with no one batting an eyelash.

I think that's sexist and awful and all that, but British people don't experience it the same way. That doesn't make sense (to me), but emotional reactions to words don't always makes sense.

I think it's appropriate and good that you're explaining to people why spazz is not an unacceptable profanity in Black American culture. But when you're dealing with people who have been conditioned since childhood to be shocked by the word, communication isn't going to be easy.