I actually kind of know the answer to this. There is a common misconception that Mussolini's "corporatism" is the influence of corporations in the business and policy of the state, which is how the word is overwhelmingly used today. In all actuality, what Mussolini meant by "corporatism" is essentially a collection of workers unions, each of whom represent a different profession and trade, who would convene and, under guidance of the Fascist regime, aid in matters concerning the economy.

It served multiple purposes, the most significant being the absorption of workers and labor movements into the Fascist sphere of influence but it also aligned with the Fascist concept of society existing as an organic being, with different groups performing separate specialized tasks while all working together to bring about the resurrection of the nation. A useful comparison would place the Fascist concept of a "corporatist council" as a kind of nationalized version of the guild system which was pervasive in some parts of Europe during the Middle Ages.