What is an etymological dictionary?

An etymological dictionary is a dictionary in which each listing contains the history of the given word or phrase. This history can cover the language of origin, earliest known use, and any changes or shifts in the term's meaning over time.

To build an etymological dictionary, linguists who specialize in etymology trace any changes in the ways authors use a given word or term over time by comparing texts from different historical eras. Additionally, linguists may compare related languages to help determine whether a word developed from the languages shared ancestral language or was instead borrowed from a different language.