I heard a discussion on this and don’t know the answer. Is a hot dog a sandwich?

No a sandwich is slices of bread, a hotdog is made with a roll..
Ok the concept is a sandwich but it's not known that way.

Any filling in between any type of bread is a sandwich

Cooked, hot, or not it's still a sandwich

Sandwiches are bread, they are what we call Rolls in the UK.

Yeah. It's in bread.

A sandwich is defined as two pieces of bread with a filling in between (such as meat). So my next question is if a hotdog bun is considered one or two pieces of bread lol.

more like a roll with mead in it. Like a lobster roll

Close enough for me....they call subs sandwiches ….. my vote is yes a hot dog is a sandwich.

Mmm. I tend to think sandwich but it seems wrong

meat inside bread, yes.