This dictionary contains over 3800 entries, including 200 new entries, covering all commonly encountered physics terms and concepts, as well as terms from the related fields of astronomy, astrophysics, physical chemistry, and biographies of important scientists. It is generously illustrated with over 120 diagrams, graphs, and tables. Feature entries provide in-depth analysis of key topics, from crystal defects to the solar system. New to this edition are entrylevel web links and a web-linked appendix which are accessible and kept up to date via the Dictionary of Physics companion web page.