Whatever else a hood is, it isn't a Schärpe or a Stola (both of which are visible from the front). It can in fact be worn as a hood (i.e. over the head) and we did this for fun photos at degree ceremonies.
A hood, unlike a cap or gown, is specific to a particular degree (there are no such things as undergraduate hoods). As a result of the inflation in degrees in the last 40 years, there has been an inflation in hood designs too. At the older universities, one of the conventions is that all Bachelor's hoods are fur-lined, and none of the others are.
These days, academic dress is not much worn. When it was worn on a daily basis, there were rules about when hoods were worn (it was not very often, but Sunday chapel was one such occasion). The occasions are not the same as doctors' scarlet days, though they might overlap. I do have a photo of myself in scarlet and a hood, but that was just a photo op, and has never been repeated.
I think the only possible translation is 'Kapuze'.