"Moja babcia gotuje ziemniaki na obiad."

Translation: My grandmother is cooking potatoes for lunch.

[RadhaTereska]

Both of my parents used the word kartofel for potato - even though they were from eastern Poland - I think ziemniak is of slavic origin and kartofel of germanic - please correct me if I am in error.

[immery]

both are correct,

I have no idea why, but suposedly "ziemniak" was more used in south Poland (Austrian partition), and kartofel cenrtal-east (Russian partition) but then both russian and german word for potatoes are similar to kartofle

also prof Miodek says kartofel is much older word, http://www.gazetawroclawska.pl/artykul/387160,rzecz-o-jezyku-o-wyzszosci-kartofla-nad-ziemniakiem,id,t.html

[JanKLinde]

I have an idea why ;-)

Austrians usually don't say "Kartoffel", they prefer "Erdapfel" ("apple from the ground", like the French "pomme de terre"). So the people from southern Poland translated this (without the apple) into Polish.

[vytah]

That's more or less correct. The standard and most common word is ziemniaki, but most people may use kartofle interchangeably and everybody understands both words. There are other, regional words for potatoes as well, the most commonly known being pyry, used in Wielkopolska.

[Aleksandra739743]

Is it -dinner -_ obiad in Polish

[Jellei]

Depends whether you consider the three main meals to be breakfast/lunch/dinner or breakfast/dinner/supper. "obiad" is the middle one.