etymologia

Etymologia is the study of the history of words, focusing on their origins, forms, and meanings as they develop and move between languages. It is a central discipline within historical linguistics and philology, employing methods that compare related languages, trace sound changes, and analyze borrowings to reconstruct how words arrived at their current forms and senses.

The term itself derives from Greek etymon, meaning "true sense," and logia, meaning "study" or "treatise." In Romance languages the word is etimologia (Italian and Spanish), while in English the corresponding term is etymology. Etymology also informs how dictionaries explain a word’s history.

Practices include consulting etymological dictionaries, applying the comparative method, and examining phonological and semantic changes over time. Scholars distinguish inherited roots from borrowed material and track regular sound shifts. Etymology can be uncertain and subject to revision as new evidence emerges.

An illustrative case is the word etymology itself: English etymology traces back to Latin etymologia, from Greek etymologia, built from etymon and logia. Other examples show how English words with related forms in other languages reveal common ancestry and contact with other cultures.

See also: historical linguistics, philology, cognates, proto-language, etymological dictionary, linguistic change.