Complex sentence: It should not be confused with petrol (which is called "gasoline" in North America), although the two words have the same etymological origin, coming from the Ancient Greek word "petra", meaning "rock".
Split into simpler sentences: It should not be confused with petrol (which is called "gasoline" in North America). Interestingly, however, the two words have the same etymological origin, coming from the Ancient Greek word "petra", meaning "rock".