The FM Dictionary Handbook serves not just as a reference for facilities management terminology, but more importantly as a learning tool for developing deeper mastery of FM concepts and their practical application. This handbook goes beyond brief definitions to provide thoughtful explanations that illuminate how key ideas are used in real-world FM scenarios. With over 1,000 terms spanning the breadth of FM knowledge, the dictionary covers everything from HVAC to plumbing, electrical to sustainability. The clear and accessible definitions establish a common language for discussing facilities management while remaining useful for experienced professionals. Unlike a typical dictionary, this handbook is designed to aid in preparing for FM certification exams by enhancing understanding of terminology, methodology, and best practices. The insightful explications give readers valuable insight into core ideas and how they are applied in practice. Hence, the FM Dictionary is an invaluable resource not only for referencing definitions but for truly deepening expertise. As a living document, we welcome readers to recommend new terms, refine existing definitions, and share feedback to help build a comprehensive, accurate guide that serves the diverse FM community. Your contributions will enable clearer communication and collaboration to optimize the built environment. Please explore the dictionary, connect with suggestions, and share it as a learning tool and guide.