It's said you can't teach a parrot not to swear once it knows those words. I disagree completely. The theory goes parrots love the yelling and drama that goes with swear words, so once they "get" them they won't not use them. And so the warning follows to be careful what you say, because they will never unsay them.
Parrots love conversation, and they appreciate drama, at times. But they are not high voltage creatures on the whole. Whatever the reason a bird has grabbed a word has no interplay to fixing the problem. It's actually a simple process, and the process will go on as long as necessary. Every bird is different.
Felix is a fine example. He came to us with, "Fxxxing take a shower!" He said it with a big cheerful old man voice. I laughed every time he said it, trying to imagine the case it was used in. Was the previous owner trying to sell Felix on a shower? Or, possibly was the older gentleman being sold on one himself in front of Felix. We shall never know. But he LOVED saying it when he was happy, and wanting to join in a bit of conversation. It was just his happy interplay. Which was great until guests were around.
So, we set out to change his vocabulary. Every time Felix said, "Fxxxing take a shower!", we would repeat it in EXACT tone and sing song but with a new replacement word "TIME to take a shower!". At first he saw it as a game of who could say it louder. Then it was a game of who could say it faster. Then it was a game of who would use which word. 6 weeks later Felix replaced the word "Fxxxing" with "Time". He's relapsed a couple times during excitement or chaos in the house. We just mirrored back with the appropriate sentence. But it really is that easy.
You can replace a single word like "sxxt" with "sugar". When you mirror the replacement word back just use a bit more excitement and volume. Certainly the appropriate word is FAR more fun to say! It's important to remember that a HUMAN will attach meaning and intent with curse words, but a parrot only attaches that which comes back to it. Flock Calling is the mirrored exercise of voice, body and mind. It is affirmations repeated in the flock for communication, edification and direction.
So, much like there is no bad bird, there also is no bad word, to a parrot anyway.