The future-robust evolution of product portfolios is a key challenge for manufacturing companies. It requires the integration of strategic product planning and the understanding that products are developed in generations based on references following the SGE - System Generation Engineering theory. There is, though, a lack of consistent terminology that unites these topics and makes their concepts consistent. Their terms are used differently across industries, institutions, and companies. The resulting miscommunication leads to a loss of efficiency. Hence, a structured, interrelated terminology is needed. The paper contributes an ontology that delivers a unifying basis for the development of models and methods
