The European Digital Education Hub presents a comprehensive glossary defining key concepts and terms for higher education interoperability. This reference document clarifies technical terminology across education and architectural sectors, supporting stakeholders implementing the Higher Education Interoperability Framework. It covers essential concepts from authentication and digital identity to learning management systems and micro-credentials. The glossary addresses four interoperability layers—legal, organisational, semantic, and technical—providing standardised definitions for terms like joint degrees, European University alliances, and student information systems. Created by a consortium including DAAD, Deloitte, and KIC, it serves as a foundational resource for achieving seamless data exchange across European universities.