The Oxford English Dictionary–available online via the Oesterle Library wesbite–is the definitive record of how words in English are written and spoken around the world. If you want to know what a word means–or its origin and history of use going back to the Middle Ages–the OED is the place to look.

Since the English language is always changing, the OED is always, changing, too: the dictionary’s editors are constantly working to add entries for new words and revise words to reflect contemporary usage.

In the latest update of the dictionary, new or revised entries include “thingamabob,” “eco-friendly,” “retrovirus,” and even the”F-word.” If you want to check out all of the new entries, try this list from the Oxford website.