This is the 5905th most frequent Polish word.
ziemnego
"Ziemnego" means "ground" or "earthly" when used adjectivally, and can refer to "natural" in contexts like "natural gas."
The word 'ziemnego' is in the genitive form and modifies 'gaz', indicating 'natural gas'.
Rurociąg transportuje gaz ziemny od producenta do odbiorcy.
The pipeline transports natural gas from the producer to the consumer.
Here, 'ziemnym' is in the instrumental form and modifies 'sos', suggesting the sauce has an earthy character.
Na obiad zrobiłem ziemniaki z sosem ziemnym.
For lunch, I prepared potatoes with earthy sauce.
The word 'ziemnego' is in the genitive case and modifies 'ciepła', referring to 'geothermal heat', literally 'heat from the earth'.