The Oxford Dictionary’s definition of a sandwich is “two slices of bread, often spread with butter, with a layer of meat, cheese, etc. between them”. A sandwich, therefore, extends to many different things, like turkey sandwiches, bologna sandwiches, and basically any form of meat in between two pieces of bread. A hot dog, therefore, is a sandwich because the two key components of it are the meat which is placed in a sliced bun. Going by the dictionary definition, this makes the hotdog a sandwich. Now, if one was to argue that it was not a sandwich, but rather its own category, I will only agree to a certain extent. If the hot dog, as in the meat part, was on its own outside of a bun, then I will concede that it is not a sandwich, but just a hotdog. But if it is in between two pieces of bread, then it is a sandwich, not a hotdog. Compare this to something like a turkey sandwich. On its own, turkey is just turkey, not a sandwich, much like the hotdog, but in between two pieces of bread, it then becomes a sandwich.

So, if it is in between two pieces of bread, then it is a sandwich, but if the hotdog (the meat itself), is not in between two pieces of bread then it is just a hotdog.