Homo economicus
The use of the Latin form "Homo economicus" is certainly long established; Persky traces it back to Pareto (1906) but notes that it may be older. The English term "economic man" can be found even earlier, in John Kells Ingram's "A History of Political Economy" (1888). The "Oxford English Dictionary (O.E.D.)" cites the use of "Homo oeconomicus" by C. S. Devas in his 1883 work "The Groundwork of Economics" in reference to Mill's writings, as one of a number of phrases that imitate the scientific name for the human species: