I'll assume this question was asked sincerely and in good faith.

By cancelling in this context I mean trying to ostrasize those they disagree with. Talking negatively about them, excluding them as much as possible from social and professional activities. Ignoring their advice and opinion at work. Being rude or negative when they do have to engage with them etc.

In short, acting without the respect and courtesy we would want colleagues to show each other.

That's soft cancellation.

Hard cancellation is when you get others to gang up on them and go to HR to try to get them fired. Afterwards, you publicise whatever got them fired offline in the hopes that they become 'radioactive' to employers and so that they and their family fall on hard times.

I'm a little confused as to why people don't understand what "cancel" means in this context. Isn't it quite a popular topic nowadays? Is it possible that they're claiming ignorance, because they want to argue against the meaningfulness of the term?

I think people get confused because many on the right use cancellation to refer to both firing people who have done something that's truly vile, as well as those who have been fired for simply having an unorthodox opinion. E.g. Harvey Weinstein vs. James Damore.

Your comment and the comment you're replying to gave two very different definitions of "cancel". And yet you're surprised that people find it ambiguous?

It's not ambiguous in the context. And normally people don't bring the sorites paradox to definitions of words that describe gradients -- we can describe something as cancellation even when there are more severe cancellations that are possible.

The question wasn't asked in good faith, as much as I appreciate the courtesy of the respondent. You can read that user's twitter and see that they were already familiar with the term and they believe only Nazis complain about it (they posted a graphic novel panel indicating this.) They were only asking for clarification in hope of getting an answer they could exploit in some way.

I dearly wish that when people use the phrase “cancel culture,” they mean exactly what you say here. If they did, it would include trying to “cancel” people who sympathize with white nationalism.

But it would also mean people who belittle or demean others because of their gender. Or people who belittle, demean, and bully people with less experience.

One of PayPal’s founders once bragged that they declined to hire an engineer because they said they liked to “shoot hoops,” and PayPal was not a company where people liked to “shoot hoops.”

All of that would be “cancelling” people too, by your definition, and it’s all just as worthy of discussion.

Where I work, that sort of behavior is classified as "workplace bullying", and I think that's accurate. My concern with political discussions being common is that people will be expected to conform to whatever happens to be dominant in that workplace in order to remain on everyone's good side. I don't know if it would be possible to refrain from participating without being called out, because people will think you're hiding something.