A fossil is the mineralized remains of a dead organism. Fossil may also refer to:

A Pokémon trading card set (see List of Pokémon Trading Card Game sets)

Fossiles, the 12th movement in the musical suite The Carnival of the Animals by Camille Saint-Saëns

Someone or something can be called a "fossil" figuratively (often as an insult) if he/she/it is extremely old (or the views they hold/represent are seen as archaic).

Fossil, Inc., a clothing/accessories company

Fossil, Oregon, a city in the state of Oregon, United States

Fossil (file system), a file system used mainly by Plan 9 from Bell Labs

Fossils (band), a Bengali rock band

Fossilized term, a type of bound morpheme in linguistics

FOSSIL, a protocol for serial communications

Fossilization is a linguistics term which refers to permanent errors in a learner's second language.