Not long ago, I noticed the use of the word “fire” to denote good. Now it seems “disgusting” is trending. What’s next, putrid? I wonder if AI could track down the first guy to use disgusting. I’m gonna guess disgusting is way more common than I realize, being apart from humanity as I am.
Gotta keep the parents guessing. 
(I really do not know)
Disgusting is a sick (impressive) term for bad (good).
When kids these days say ‘bad’ they mean ‘good’. And to 'shake your booty" means to wiggle one’s butt.
I don’t think either of those terms are remotely new.
My 13 year old used “fire” as good for a while. It seemed to be used like “cool” in the way cool can mean something impressive, or “yes”, or “thank you”.
Lately they’ve switched to “bet”. An exchange goes something like, “hey kid, the chicken is done.” “Bet.” In my own head this is a contraction of a Minnesota “you betcha.”
I’ll have to ask about disgusting.
Yeah, it’s probably been 10+ years since I first heard “fire” to mean cool.
Who are you replying to? The OP, or the post just before yours?
They are the same person. But I think it was obvious the post just before mine.
Actually, it wasn’t obvious to another poster who replied to you, so I wasn’t sure which post you were replying to. It helps to quote part of it so it’s clear. Especially since the post just before yours looked like a whoosh.
It was obvious.
What else did you possibly think it referred to?
This board sometimes…
Not to the poster who replied to you.
I’m still stuck on “gear” and “fab”.
(No I didn’t watch ~Hard Days Night~ today)
The OP had two posts.
I replied.
Not my problem if someone else does not follow. That’s on them. I think my posts were clear.
I’m done with this argument.
The pattern where words flip meaning (especially from negative to positive, but sometimes the other way) is very old. ‘Terrific’ used to mean causing terror; ‘prestigious’ used to mean deceptive; ‘nice’ has gone through a series of changes from foolish/stupid to fussy to pleasant and in the other direction, ‘awful’ used to mean majestic/worthy of great respect (same as awesome).
So you’re saying that fire as cool is now so old it’s cold? 
The post above yours was so obviously a joke.
I can’t speak for the OP. But my experience is that if you aren’t on social media a lot, don’t do online gaming, and generally maintain a Year 2005-style Internet existence … the first time you start hearing 2015’s teenage slang is in 2026 when late-twenty-somethings enter your workplace (or other meatspace social domain).
For me, widespread use of “fire” reached my ken around 2021-22. I had teenagers at the time, and neither one ever picked up this particular slang. My now-daughter-in-law says “fire” frequently, though.
In sports, “filthy” to describe “a great play, esp one that embarrasses an opponent” goes back at least to the 1980s. Every so often, you’ll hear a Gen X color commentator (most commonly in basketball) break out “filthy”.
Being British, you probably are familiar with 101 ways to serve the word “brilliant”.