 See Robinson 1950 for a critical discussion of the different activities that have been subsumed under “real definition,” and see Charles 2010 for ancient views on the topic. Fine 1994 defends the conception that a real definition defines an object by specifying what the object is; in other words, a real definition spells out the essence of the object defined. Rosen 2015 offers an explanation of real definition in terms of grounding: the definition provides the ground of the essence of the object. The meaning of ‘essence’ and of ‘ground’ remain under active debate, however.