The term fissile is distinct from fissionable. A nuclide capable of undergoing fission (even with a low probability) after capturing a neutron of high or low energy[5] is referred to as fissionable. A fissionable nuclide that can be induced to fission with low-energy thermal neutrons with a high probability is referred to as fissile.[6] Fissionable materials include also those (such as uranium-238) for which fission can be induced only by high-energy neutrons. As a result, fissile materials (such as uranium-235) are a subset of fissionable materials.

In the film, when Robert I tells his brothers about his plan to start a rebellion, artichokes can be seen on the table. However, artichokes were not introduced to the British Isles until the 16th century.[33]