I think for the most part, other than on mental health type websites, generally, people use the words 'narc' and 'toxic' quite loosely meaning basically a very selfish, horrible, abusive type of person. At least that's the impression I get. And to that extent it probably is a fairly accurate description of their perception of the person - or at least, I'd give them the benefit of the doubt about that. Because I wouldn't take it as a literal psych evaluation of the person unless otherwise stated. 'Narc' and 'toxic' are basically general terms. But people can quite easily slap a label on others using those terms too, if they're say hurt or upset with someone. It happens. That's what I see on the internet.