While micromobility has seen a significant rise of interest across policy, industry and academia, a detailed conceptualisation of it has so far been missing from the scientific literature. This paper develops a multi-dimensional conceptualisation of micromobility, in conjunction with a new socio-technical definition. To do so, it reviews related concepts; it analyses how the term micromobility has been used; and it critically engages with existing definitions most frequently cited in this literature. Building on these insights, we develop a multi-dimensional conceptualization of micromobility. Our definition of micromobility covers a wide range of mobility options that can typically be manoeuvred by one human without motor assistance, at least for short distances, and that are ‘micro’ in terms of energy demand, environmental impact, and use of road space, relative to automobility. According to our conceptualisation, micromobility modes comprise fully human powered, partially motor assisted and fully powered options. They typically do not exceed 25 kilometres per hour (or 45 for faster ones) and weigh (often significantly) less than 350 kilogram, while often providing some (public) health benefits. Trip lengths are typically less than 15 kilometres and daily distance travelled less than 80 kilometres. This new definition has relevance for future transport and mobility scholarship, as well as policy and evaluation. Advantages of a new and widely accepted definition and conceptualisation of micromobility could include more robust design standards, legislation, as well as evaluation metrics and methods, all leading to greater understanding of, and attention paid to, this form of mobility. This paper highlights the important role that micromobilities could play in moving beyond automobility, to create more sustainable and just mobility futures.