@HonoraryMancunian It’s about a yarn bowl which has an indentation on the side to pull your yarn out. The indicated diameter is the diameter of the bowl and how far you can pull the yarn out without the bowl toppling or the ball falling out.
A flawless out of context boost by @knitting:
@quinacridone Hope you enjoy! I love their patterns and my self-taught knitting journey started with their incredible beginner's guides. I learned socks with their tutorial too and every pair I've done has turned out perfect.
@quinacridone You would absolutely love Tin Can Knits. They have tons of written guides for beginners with pictures, and videos aren't mandatory in any way.
@Mouselemming My mobile client seems to automatically do it, I haven't done it myself. I just hit reply as it shows on my feed :)