I always assumed "toxic" means that it affects others it comes into contact with.

e.g. You've had a bad day at work:

Negative: Being a bit withdrawn and avoiding conversation

Toxically negative: Shouting at your wife and kids

I'd be a bit more charitable .. I'd label it as toxic if the extreme negative behaviour was a regular occurrence.

I think this is quite a good definition. After all, it's a key principle of toxicology - courtesy of Paracelsus - that the dose makes the poison. (Any woman who's had Botox can attest to this.) It certainly seems to be used that way in this article, in being applied to 'positivity'.

Except then it also becomes a label to classify the undesirable as extremist.

"Extremist" is a problem too. In 1787 banning slavery was an extremist position in the world.

Maybe so! .. but more likely a narcissist or sociopath in my experience.

As often as not, those are precisely the people using these weapon words.

Like toxic skiing? Or toxic mountain climbing? Toxic marathon running?

Hi, this put a smile on my face imagining it being used in place of 'ultimate'. Toxic Frisbee. :)

I guess the definition should be revised to "extreme behaviour, directly having an overbearing effect on another person's wellbeing".

Maybe there could also be a side definition for running competitively in a nuclear contamination zone though!

Now that I think about it, toxic endurance sports hits too close to home...

Toxic = excessive to the point of being harmful