(קאַרק דער (עס/קערק - neck, nape

That's the entry in Beinfeld/Bochner Dic..

Playing with my phantasy, I would think: Cork from the tree is the rind of a treee, so maybe they mean the bread's crust. Or maybe, when it's neck or nape it´is the top side of a loaf of bread or another area.

Huh, bread ends/crusts.

I wonder if it is based on the Slavic word 'kor' meaning 'bark' with the Slavic feminine diminutive ending -ke and the plural -s.

I could see how bread crust resembles the bark of a tree (the outer casing), so maybe that is the etymology of the word.

The word I was thinking of for 'bark' is actually 'kore', so my guess might be off there, but even if it is, I am still suspicious of the -ke- and would be a little surprised if it isn't the diminutive Slavic suffix.

I finally fought my Russian dictionary back out of the closet and it looks like korke (Russian корка) is from the word kore (Russian кора) with the diminutive -ke suffix. The dictionary I am using, Harper Collins Russian Concise Dictionary, glosses корка only as 'peel,' 'scab' and in an expression meaning 'to read something from cover to cover', but it refers back to kore Russian кора which is glossed as 'bark,' 'cortex' and in expressions for 'the earths crust' and 'cerebral cortex.'

As the title of this dictionary indicates it is Concise, so it probably just fails to list the meaning with bread crusts, but the semantics are there, right down to the word 'crust.'

Al dos guts,
Yosele