W131: English Composition: Reference Materials

The Encyclopædia Britannica, published by Encyclopædia Britannica, Inc., is a general knowledge English-language encyclopaedia.

Free online dictionary of English language information as provided by Merriam-Webster, which has published dictionaries for over 150 years.

The Online Etymology Dictionary is a free online dictionary that describes the origins of English-language words.

The Oxford English Dictionary (OED) is a historical dictionary of the English language, published by Oxford University Press (OUP). It traces the historical development of the English language, providing a comprehensive resource to scholars and academic researchers, as well as describing usage in its many variations throughout the world.