The Cambridge Encyclopedia of the English Language
Reference: 420 C889c2

Explanations of the history, structure, variety, and range of uses of English.

The Oxford English Dictionary (Online)

The OED online provides access to the entire 20-volume Second Edition of the Oxford English Dictionary and the 3 volumes of Additions. It includes authoritative definitions of over 500,000 words, traces word usage through history, offers etymological analysis, and provides detailed listings of variant spellings.

The Oxford Dictionary of English Grammar
Reference 428 C351o

Helpful definitions of 1,000 grammatical terms with examples.

The Johns Hopkins guide to Literary Theory & Criticism
Reference 801.95 J622g2

Guide to important figures, schools and movements in literary theory and criticism.

Encyclopedia of Folklore and Literature
Reference 803 En19b

Contains entries for authors, titles, national literatures, themes and motifs in literature and folklore.

A Handbook to Literature
Reference 803 T41h5

An alphabetical listing of important terms and facts in literature, linguistics, rhetoric, criticism, printing, bookselling, and information technology.

Encyclopedia of Medieval Literature
Reference 809.02 En19L

Covers authors, specific works of literature, major historical figures, and major events from A.D. 500 to A.D. 1500.

Literature and Its Times: Profiles of 300 Notable Literary Works and the Historical Events that Influenced Them
Reference 809.9 L712m

Explores the historical events and pertinent social customs during the time in which each work is set as well as when it was written.

All Things Shakespeare: an Encyclopedia of Shakespeare's World
Reference 822.33 G OL8a

Entries describe various aspects of Elizabethan England, including common objects, daily activities, popular beliefs and attitudes, and place them in the context of the plays.