Comment by selcuka

> Does that reflect the Turkish terminology?

Yes. The Turkish terms are "kalın ünlü" and "ince ünlü". They literally translate to "low pitch wovel"/"high pitch wovel" )(or "thick wovel"/"thin wovel") in this context.

There is a second wovel harmony rule [1] (called lesser wovel harmony) that makes the distinction you pointed out. Letters a/e/ı/i are called flat wovels, and o/ö/u/ü are called round wovels.

[1] https://georgiasomethingyouknowwhatever.wordpress.com/2015/0...