The RDA I-ADOPT framework offers a way to compile clear and unambiguous definitions of variables in a standardised way. It helps you to describe concepts at different levels, ranging from overarching classes (“soil composition”) down to the very detailed (“soil water content, measured in a mineral soil matrix below root depth”).  You can create and register your own definitions, or reuse those of others, and once in place use them to tag your RI’s datasets.The formalized descriptions empower FAIR in many ways, for example by facilitating searches across data portals (F+A) and enabling machine-driven interpretation and use of data and metadata (I+R).