J.R.R. Tolkien worked as an editor's assistant on the OED after serving in World War I. His job was to look into the etymologies of words beginning with the letter w. Tolkien also wrote multiple definitions for words like waggle, walnut, walrus, and waistcoat. Tolkien went on to work as an English professor and write The Lord of the Rings after leaving the OED. Following that, the OED has added terms coined by Tolkien himself, such as hobbit, mithril, and mathom.