Medical Extended Reality (MXR) is a dynamic field at the intersection of healthcare and immersive technologies, encompassing virtual, augmented, and mixed reality applications across various medical disciplines. Despite its rapid growth and recognition by regulatory bodies, the field lacks a standardized taxonomy to categorize its diverse research and applications. The American Medical Extended Reality Association (AMXRA), in collaboration with the editorial board of the *Journal of Medical Extended Reality*, has developed a comprehensive taxonomy for MXR. This taxonomy, authored by a multidisciplinary and international panel of experts, aims to standardize terminology, categorize existing work, and provide a structured framework for future research and development in MXR. The taxonomy comprises 13 primary topics that expand into 180 secondary topics, covering the breadth and depth of MXR. The five overarching domains are: (1) technological integration and innovation, (2) design, development, and deployment, (3) clinical and therapeutic applications, (4) education, training, and communication, and (5) ethical, regulatory, and socioeconomic considerations. These domains serve as foundational themes that link the various components of MXR, providing a hierarchical view of the field. The development process involved an iterative approach, with input from experts based on publication track records, contributions to MXR, and other objective measures. The final taxonomy is intended to be a living document, open to modifications and expansions to reflect ongoing advancements in the field. This taxonomy will serve as a foundational tool for researchers, clinicians, funders, academic publishers, and regulators, facilitating clearer communication and categorization in the rapidly evolving field of MXR.Medical Extended Reality (MXR) is a dynamic field at the intersection of healthcare and immersive technologies, encompassing virtual, augmented, and mixed reality applications across various medical disciplines. Despite its rapid growth and recognition by regulatory bodies, the field lacks a standardized taxonomy to categorize its diverse research and applications. The American Medical Extended Reality Association (AMXRA), in collaboration with the editorial board of the *Journal of Medical Extended Reality*, has developed a comprehensive taxonomy for MXR. This taxonomy, authored by a multidisciplinary and international panel of experts, aims to standardize terminology, categorize existing work, and provide a structured framework for future research and development in MXR. The taxonomy comprises 13 primary topics that expand into 180 secondary topics, covering the breadth and depth of MXR. The five overarching domains are: (1) technological integration and innovation, (2) design, development, and deployment, (3) clinical and therapeutic applications, (4) education, training, and communication, and (5) ethical, regulatory, and socioeconomic considerations. These domains serve as foundational themes that link the various components of MXR, providing a hierarchical view of the field. The development process involved an iterative approach, with input from experts based on publication track records, contributions to MXR, and other objective measures. The final taxonomy is intended to be a living document, open to modifications and expansions to reflect ongoing advancements in the field. This taxonomy will serve as a foundational tool for researchers, clinicians, funders, academic publishers, and regulators, facilitating clearer communication and categorization in the rapidly evolving field of MXR.