For instance, I am writing a paper in which I am arguing that the Ancient Greek mythological Harpies originated as personifications of the Sirocco (dry wind from the Sahara). The Harpies are the personifications of the Sirocco; the Sirocco is the _______ of the Harpies.
The closest I can come up with is the term "signified" from semiotics, but this doesn't really work. I've even tried "counterpart," but ehhhhhh, so unspecific. Anyone have any better ideas?