Eternal Erteple (5th @ Eternal Championship)

Czech for potato is "brambor" – from German state of Brandenburg, as that's where it got introduced from. German "kartoffel" comes from Italian "tartufo" meaning truffle, because that's a brown edible dug up from ground and apparently totally the same thing.

In Moravian Slovakia where I come from, we call them "erteple" from Austrian German Erdäpfel (earth apples). Funnily, the Croatians and other Shtokavian speakers also borrowed from Austrian – "Grundbirne" – a ground pear, giving them krumpir/krompira/кромпир.