The Oslo definitions for coeliac disease (CD) and related terms were developed by a multidisciplinary task force of 16 physicians from seven countries. The goal was to establish clear, consistent definitions for CD and related terms to improve communication and research. CD is defined as a chronic small intestinal immune-mediated enteropathy triggered by dietary gluten in genetically predisposed individuals. Classical CD is characterized by signs and symptoms of malabsorption, such as diarrhea, steatorrhea, weight loss, or growth failure. The term "gluten-related disorders" is proposed as an umbrella term for all diseases triggered by gluten, and the term "gluten intolerance" should not be used. The paper outlines definitions for various CD-related terms, including asymptomatic, atypical, classical, latent, non-classical, overt, paediatric classical, potential, refractory, silent, subclinical, and symptomatic CD. It also defines gluten, gluten ataxia, gluten sensitivity, non-coeliac gluten sensitivity (NCGS), and other related conditions. The definitions aim to clarify the spectrum of gluten-related disorders and provide a foundation for clinical management and research. Key definitions include: CD is a chronic disease, but transient CD may occur. Asymptomatic CD is not accompanied by symptoms, while subclinical CD is below the threshold of clinical detection. Typical CD is discouraged as it implies a most frequent form, while atypical CD is not recommended due to confusion with non-classical CD. Refractory CD is defined as persistent or recurrent symptoms despite a strict gluten-free diet. Gluten autoimmunity is defined by positive TTG or EMA on at least two occasions. The paper also addresses the importance of accurate terminology to avoid confusion and ensure consistent research and clinical practices. Definitions are provided for gluten-related disorders, including gluten ataxia, dermatitis herpetiformis, and NCGS. The study emphasizes the need for standardized definitions to improve diagnosis, treatment, and research in CD and related conditions.The Oslo definitions for coeliac disease (CD) and related terms were developed by a multidisciplinary task force of 16 physicians from seven countries. The goal was to establish clear, consistent definitions for CD and related terms to improve communication and research. CD is defined as a chronic small intestinal immune-mediated enteropathy triggered by dietary gluten in genetically predisposed individuals. Classical CD is characterized by signs and symptoms of malabsorption, such as diarrhea, steatorrhea, weight loss, or growth failure. The term "gluten-related disorders" is proposed as an umbrella term for all diseases triggered by gluten, and the term "gluten intolerance" should not be used. The paper outlines definitions for various CD-related terms, including asymptomatic, atypical, classical, latent, non-classical, overt, paediatric classical, potential, refractory, silent, subclinical, and symptomatic CD. It also defines gluten, gluten ataxia, gluten sensitivity, non-coeliac gluten sensitivity (NCGS), and other related conditions. The definitions aim to clarify the spectrum of gluten-related disorders and provide a foundation for clinical management and research. Key definitions include: CD is a chronic disease, but transient CD may occur. Asymptomatic CD is not accompanied by symptoms, while subclinical CD is below the threshold of clinical detection. Typical CD is discouraged as it implies a most frequent form, while atypical CD is not recommended due to confusion with non-classical CD. Refractory CD is defined as persistent or recurrent symptoms despite a strict gluten-free diet. Gluten autoimmunity is defined by positive TTG or EMA on at least two occasions. The paper also addresses the importance of accurate terminology to avoid confusion and ensure consistent research and clinical practices. Definitions are provided for gluten-related disorders, including gluten ataxia, dermatitis herpetiformis, and NCGS. The study emphasizes the need for standardized definitions to improve diagnosis, treatment, and research in CD and related conditions.