the OP is confused. A medical degree is called different things in different countries, but it means the same thing irrespective - a undergraduate qualification in medicine.
If you graduate from most UK universities, the degree is: MB,BS. Some UK universities call it something else, for example at Oxford it is: BM,BCh. (Oxford must always be different! Their PhD is called DPhil). Cambridge awards MB,BS. I think in Ireland, the medical degree is called MB,BCh,BAO. What a mouthful!!
Most countries in the world follow the UK system because the Brits set up their universities when they ruled over the Empire, so that if you graduate from Australia, NZ, most of Europe and Asia, it is called MB,BS.
In the US, all schools grant the MD. (I think McGill is the only American school that calls it MDCM)
Bottom line, they all mean the same thing - the recepeient has obtained a basic undergraduate professional degree in medicine.
The word "doctor" and "doctorate" is much abused and misunderstood here in the US. I personally don't think many of the "professional" "degrees" should carry the title doctor. The word is so cheapened. Nowadays, optometrists and podiatrist call themselves "doctor". Even chiropractors, which is basically one of the most successful quack institutions of all time actually call themselves "Doctor". And of course the naturopaths, etc.
In the rest of the world, UK, Europe, Austrlia, Asia, the only people who can legally call themselves doctors are holders of a true doctorate (ie PhD/DPhil/DSc), or medical doctors.
But we Americans have an anti-elitist impulse, so we spread the joy.
