This is the 5463rd most frequent Polish word.
talerzu
"Talerzu" means "plate" in English (locative case).
In this sentence, 'talerzu' is in the locative case, indicating the location where the apple is situated—on the plate.
Na talerzu leży jabłko.
There is an apple on the plate.
Here, 'talerzu' is used in the locative case to specify the location of the food being referred to—the plate.
Nie dotykaj jedzenia na moim talerzu!
Don't touch the food on my plate!
In this example, 'talerzu' again appears in the locative case, used to describe an attribute (design) found on the plate.