A particularity about the literature on the meaning of work is that the concept of meaning is discussed extensively and deeply, while the concept of work is hardly debated at all. Tackling this shortcoming, we start out by taking up contradictions in the social science debate on definitions of the concept of work. Four such contradictions stand out: (1) Subjective vs. objective definitions; (2) a single vs. several work concepts; (3) certain activities in themselves vs. any activity within specific social relations are to be regarded as work; and (4) empirical vs. ontological basis of the concept. In investigating them, we take help from what are often said to be the three most important classics of social science: How have Émile Durkheim, Max Weber and Karl Marx handled the concept of work? Specifically, can we get inspiration from them to take stands concerning the contradictions? The answers to these questions lead us to suggest this definition: Work is any activity performed in internal social relations that structure the sphere of necessity. Finally, we discuss the three suggested explicit conceptualisations of ‘work’ that we have found in the meaningful work literature.