noun, plural: fossils
Having the characteristic, or pertaining to the nature, of a fossil.
Fossils include shells, imprints, burrows, coprolites and organically-produced chemicals. The oldest fossils were bacteria that existed 3.8 billion years old. Fossils are once thought of to be all from extinct species until some were found to belong to species that are still living.
Word origin: from Latin fossilus, (something dug up)