Etymology is an account of the history of a particular word or element of a word.
Through old texts and comparisons with other languages, etymologists try to reconstruct the history of words — when they entered a language, from what source, and how their form and meaning changed.
An Etymologist is different then a philologist, one who studies linguistics and etymology.
Beware, those who are nescient often misuse and mispronounce'entymology' which is actually the study of insects!
Denise: If we had resources available to us, we could hire an etymologist to do our homework!
Kenny: Let's just log onto youtube and watch HotForWords...
Denise: Isn't she a philologist?