[M Clayton]

I don't know that I can recommend a dictionary to read but the medical defense societies usually give away a copy of the Oxford Concise Medical Dictionary at some stage during your first year. On that basis, I wouldn't buy one - the internet is usually sufficient if you don't get a freebie copy...

There are plenty of medically related books out there that you could conceivably read for pleasure- Bodies, Sick Notes, The House of God, Stiff, In Stitches and Blood, Sweat & Tea are just a few that immediately spring to mind.