Crossword clues for the word: FOSSILFUELS The word FOSSILFUELS has appeared as an answer to at least 3 crossword clues on different crossword puzzles. Crossword clues for FOSSILFUELS Showing 1 to 3 of 3 results Clue(s) "Combustible organic materials, such as oil and coal, that may be key contributors to global warming: 2 wds." "Energy sources formed in the earth from organic remains, as coal or oil: 2 wds." Nonrenewable natural resources such as coal and petroleum: 2 wds.