IIRC, with respect to hypertext as a concept rather than specific HTML specs/implementations, hyperlinks were sometimes envisioned (implemented?) as being bi-directional references. As such, you needed an element on each end of the reference that pointed to the other end.
In thinking of "href" as "head reference", you are providing a URI (possibly also a target URL) from your source document -- the tail -- to the intended destination, the head.
I'm unclear what this looks like from the head's perspective. Is the tail/head distinction absolute, or relative and dependent upon the current document's perspective? If absolute, then the tail might be viewed as the link's instantiator.