Emily Dickinson Lexicon

FOS'SIL, a. [Fr. fossile; Sp. fosil; It. fossile; L. fossilis; from fodio, fossus, to dig.]

1. Dug out of the earth; as, fossil coal; fossil salt. The term fossil is now usually appropriated to those organic substances, which have become penetrated by earthy or metallic particles, and are found in rocks or the earth. Thus we say, fossil shells, fossil bones, fossil wood. – Cleaveland.
2. That may be taken from the earth by digging.