Word of the day: hack

I'm currently reading the anthology London: City of Disappearances, edited by Iain Sinclair. One of the essays in the collection, Alan Wall's 'Grub Street', has a lot of interest to say on the word 'hack' (as in hack writer or journalist).

If I could, I'd share the entire essay with you, but here are a couple of extracts:

Deriving as it does from a hackney horse, as in hackney carriage, and therefore something put out to hire, the term [hack] is used throughout the eighteenth century to mean a sorry creature, raddled and worn-out, a jade.

Johnson's Dictionary doesn't refer to writing at all under his entry for Hack; it is merely a matter of putting oneself out for hire. But the next meaning of the word listed, and one that was current at the time, is prostitute, for the hack sold his brain and his lexicon in exactly the same way that a drab sold her body.