Would it be correct to say it's a quadratic complexity causing the run time to grow exponentially? Or is the word exponential still wrong here. My Mathematics terminology is rather.. dusty.
That is wrong, because quadratic means that the variable is in the base, while exponential will tell you, that the variable is in the exponent (just as the name tells).
That makes a lot more sense! Actually rings a bell from when I ran in to the same wrongly-remembered wording in uni.
I'm not sure why, but getting back to the right terminology/vocabulary just to get back in to the basics of mathematics is a lot harder for me than it was 20 years ago.
If you casually want to get into it without the commitment, I've found that even passively watching the Tim Roughgarden videos from Coursera (probably can be found crossposted to YouTube by third parties) to be stimulating in the past.
If you seek to acquire formality and rigor, I can't help you there; I figure shortcuts will be nonexistant ;)
Don't fret it. Imo people are being unnecessarily curt when trying to flex their pedantry here, which we all love to do, myself included.
Of course, poly still means there is an exponential in the time complexity.
It's really nothing beyond the main takeaway that the usual norm to describe something as having "exponential" growth is that the number of computations increases in order of magnitude every time you add but a single item to the list of inputs.