100% a curiosity question, but I recently stumbled across some older blog posts about a silly debate of "should you eat all your pizza crust?" and I was surprised to see the phrase
Most of the time when I've seen the word crust its' been クラスト or パンの皮.
So as more of an etymological inquiry, does anyone know how exactly 耳 end up meaning crust or edge?
My usual Jisho and Wiktionary sources are leaving me dry and through my own search, I could find plenty on the Chinese etymology with 耳's relation to ear. Likewise it's obvious how selvage, crust, and edge are all related, but I couldn't find anything that connects the two. Seeing as both ピザの耳 and パンの耳 are used, I'm not sure if it's something that would trace back to the introduction of (Western) breads or pizza to Japan (since who knows which usage came first) or is something as simple as 'ears are on the edge of your face'.