Sure. Had the Normans been the only outside group coming to the British islands after Rome left it would be fine to call them Norsemen, Germanics or even just c

Sure. Had the Normans been the only outside group coming to the British islands after Rome left it would be fine to call them Norsemen, Germanics or even just continentals, but due to the long sequence of invasions it is very reasonable to use and expect the most specific terms. The word "poultry" certainly did not come on a boat before 1066, and only on a very specific subset of the boats that came that year.