When working in the highly technical fields of astronomy and the related space sciences, the practitioner is constantly confronted with a baffling array of different abbreviations, acronyms, contractions, and symbols. The identification and differentiation of these terms is a task which, all too often, can prove to be a near impossible one. With over 140,000 separate dictionary-style entries, and over 20 years in collation, StarBriefs 2001 represents the most comprehensive and accurately validated collection of abbreviations, acronyms, contractions, and symbols within astronomy, related space sciences and other related fields. As such, this invaluable reference source (and its companion volume, StarGuides 2001 should be on the reference shelf of every library, organisation or individual with any interest in these areas. Besides astronomy and space sciences, related fields such as aeronautics, aeronomy, astronautics, atmospheric sciences, chemistry, communications, computer sciences, data processing, education, electronics, engineering, energetics, environmental, geodesy, geophysics, information handling, management, mathematics, meteorology, optics, physics, remote sensing, and so on, are also covered when justified. In addition, there are separate sections devoted to Greek letters, mathematical symbols, special signs and characters, as well as to entries with a numerical prefix. Finally, terms in common use and/or of general interest have also been included where appropriate.