For what it's worth arguing about
what word to call what gun....

Let's move from English to Spanish and things just got more complicated.....
Here in Peru, all airguns that are not airgun pistols are called "carbines" [Spa:
carabinas], including long rifles, short rifles, semi-bullpups, bullpups, you name it — all "carbines"!!
The most useful naming distinction — in my mind — would be one that defines
➊ those characteristics of the gun that affect performance (performance definition) —
rather than
➋ what the original state of the gun was (historical definition).
For example:
➊ Performance Definition: Name definition using the gun's characteristics that affect performance: ▪ Barrel length: It seems like a distinction could be made between
carbine (short rifle) and
rifle (or long gun). Maybe at 500mm (20")?
▪ Excess stock length [any non-bullpup has a lot of that]: The current distinction between rifle and bullpup is helpful, and there are
compact bullpups and
regular bullpups and
semi-bullpups (the latter are still in search of their true identity).
▪ Pistols: It seems like a distinction could be made here between
long pistol (e.g., PRod) and
short pistol (e.g., GK1), or
bench pistol and
handgun. ➋ Historical Definition: Name definition based on what the gun originally was before the modification: ▪ a pistol that received a shoulder stock ➔ I would prefer to call that a rifle (or carbine)
▪ a long rifle where the shoulder stock was cut off ➔ I would prefer to call that a "pistol"
Just my 2 cents — but after adjusting them for the inflation rate we have in Peru, I'm not sure what it's worth....
Matthias