Transforming semi-structured life science diagrams into meaningful domain ontologies with DiDOn

► We propose the DiDOn procedure to speed up and simplify bio-ontology development. ► DiDOn micro-level manages the formalisation of semi-structured life sciences diagrams. ► DiDOn uses a foundational ontology for more precise and interoperable subject domain semantics. ► The procedure is illustrated with Pathway Studio as case study.