The "Dictionary of Physics" is a major reference source in the vast and dynamic field of physics that caters for both the undergraduate and graduate student. Spanning the space between the primary literature and educational texts, it encompasses 16,000 entries and 1.8 million words in four volumes. It provides exhaustive coverage of all the core areas of physics, and comprehensively examines many applied and cross-disciplinary areas. Entries vary with respect to length and complexity. "Definitions" (50-100 words) include a headword plus concise definition and cross-references to related entries. "Description Entries" (400-500 words) included a headwords with a concise definition or abstract, plus a detailed discussion with references. "Topical Entries" (3,000+) include a headword and a concise definition plus an extended essay on an overarching topic with references and further reading.