Fossil (noun)

1. The remains or impression of an organism that lived in a past geological age, embedded and preserved in rock.
2. A remnant or trace of an organism of a past geologic age, as a skeleton, footprint, etc.
3. A fuel derived from the remains of ancient plants and animals, such as coal or petroleum.

Origin:

From latin fossilis, literally "dug up", from fodere ("to dig"), from proto-indo-european *dheh₁- ("to put, place, set").

Examples:

1. The fossil of a dinosaur was found in the desert.
2. The fossil record provides evidence of evolution.
3. He was interested in collecting fossils.
4. Fossil fuels are the primary source of energy in the world.
5. The fossilized remains of ancient life forms are found all over the world.