Archaism

1. (a.) Obsolescence; an antiquated or old-fashioned word, expression, or idiom; a word or form of speech no longer in common use.

2. (a.) Antiquity of style or use; obsoleteness.

Thesaurus Entries

Pre-Raphaelitism, ancient manuscript, antiquarianism, antique, antiquity, archaeology, archaicism, artifact, cave painting, classicism, eolith, fossil, medievalism, mezzolith, microlith, neolith, obsolete, obsoletism, paleolith, petrification, petrified forest, petrified wood, petroglyph, plateaulith, relic, reliquiae, remains, ruin, ruins, survival, vestige