So immersed is Marx's rhetoric in the Gothic that Derrida in Specters of Marx creates a neologism for Marx's ontology, transforming it into “hauntology.” Marx argues that in a market economy a ghostly web of simulacra of relationships, exchanges, and circulation hovers over the whole system, indicating that people have had their humanity drained out of them by capitalism and that they are left as ghostly shells.
Source: wiktionary