Technically speaking I think it's originally French actuallythe Old English equivalent is actually "git" or "get"
That said, Bastard Gemsbok was always English, it just fell out of fashion.
An old-fashioned name in English for Roan Antelope (and still the current name in German) is "Bastard Gemsbok"
So does that mean Gemsbok is actually a French turned English turned German word?
~Thylo