[zacharycohn]

Yes, progressive vs regressive taxes are a technical term.

[jdonaldson]

Yes, but I think it's a relatively new or transient interpretation. I couldn't find much of an authoritative basis for it. It would be great if you could post any links that you know of.

There's a wikipedia article on it, but none of the key references exist any more : https://en.wikipedia.org/wiki/Regressive_tax

[eschutte2]

"The technical term for such taxation is regressive taxation" - Seligman 1894 https://www.jstor.org/stable/pdf/2485696.pdf