Information from the Appendix Probi added. Cognates from Anatolian languages (Hittite, Luwian, Palaic, etc...) and Messapian were checked for accuracy. Material from Trask and Mitxelena on the Basque language was added, though much of their vast scholastic output remains unprocessed. Behind-the-scenes, we updated several security features.

Over 300 lemmata added. We had been working on these words and affixes for over a month. We lovingly call this update the "auto"-update because we finally added all of the words beginning with the suffix auto- "self."

Over 200 lemmata added and 22 new sources consulted. While those numbers reflect a great deal of work, the majority of our labor was spent on revising already-existing material: every entry received a much-needed re-formatting; erroneous cognates were corrected; and writing was edited for grammar and tone.

Welcome to the Online Etymological Dictionary of Spanish (OEDoS), a free etymological dictionary of the Spanish language launched on August 6, 2016. An etymology is not a definition but a history of a word over time. This site provides an account of the development of the Spanish language as best as historical linguists are able to ascertain in a way that is accessible both by laymen and academics. If you enjoy using this dictionary, please consider donating to help keep this site alive.