The Glossary consists of key terms used in YOUNG_ADULLLT to sharpen our common conceptual understanding of key ideas that are of central interest to the project. It supports the interdisciplinary approach of the project not by providing homogenized definitions, but rather by pointing out the different understandings and usages across national and cultural spaces and disciplinary traditions. The Glossary reflect the collaborative work process in YOUNG_ADULLLT and helps us ensure a coherent theoretical and methodological conceptualization of the research, thus allowing the construction of a strong and innovative international and comparative research design.