I also agree with this and I agree with the OP about using the word "toxic". Personally, I prefer keeping it simply to me and my boundaries. "This person is not healthy for me to be around." or "Being around this person makes me uncomfortable." etc. Versus a blanket statement that sort of condemns them. It's the same with workplaces. What may not work for one person in an employer's culture could be totally fine for another.

What I don't like about using that word in such a blanket way, which I see often used, is that it's used like a label rather than as you are suggesting, which is how they impact you personally. I think it has become a buzz word to label people and "other" them versus try to overcome poor communication and build relationships.

I've met a few people who others might consider toxic, and even who at one point I felt like my relationship with them was toxic. But through communication and understanding, have built strong relationships with these people. I think people jump to calling anyone they have a conflict with "toxic" so they don't have to deal with the conflict and try and find resolution.

There's a newer person who works for one of my clients, and she definitely can grate my nerves from time to time because she can be very resistant to new ideas. But I also know, from having talked to her a lot, that her resistance comes from a place of uncertainty and fear about what it will mean for her work load, will she be able to gain competency in new tasks, and will there be any one to support her in new work. Knowing that, I know how to overcome her resistance and make sure she is supported when we take on new work. I learned how to make her an ally.

Her resistance and attitude could be considered toxic by some. I don't think that's the case though.

So I guess what I'm saying (forgive my rambling) is that IMO people often use labels to write things off and excuse themselves from dealing with conflict.