There is no real difference. R/D longbow, hybrid, non-contact recurve, semi-recurve... all the same. Various amounts of deflex coming off the riser (ranging from none to extreme) and varying amounts of reflex in the limbs - the string only touches at the tips.
You get some guys calling a bow a hybrid if it has a pistol grip on it and a r/d longbow if it has a straight grip... doesn't make sense to me, since it's the limb profile that determines what a bow is, not the grip.