Car Knocker said:
Where did you derive this definition from? It doesn't match any official definition I've run across.
Since you asked:
Definitions for firearm
from wikipedia
"A firearm is a device that can be used as a weapon
that fires either single or multiple projectiles propelled at high velocity by the gases produced through rapid, confined burning of a propellant. This process of rapid burning is technically known as deflagration."
from merriam-webster
"a weapon from which a shot is discharged by gunpowder —usually used of small arms"
(gases produced by burning gunpowder are considered a propellant the last time I checked.)
from dictionary.com
n. A weapon, especially a pistol or rifle, capable of firing a projectile and using an explosive charge as a propellant.
Definitions of gun:
dictionary.com
any device for shooting something under pressure: a paint gun; a staple gun.
(this is the 4th definition, the previous 3 are synonymous with the definitions for firearm)
from google
a weapon that discharges a missile at high velocity (especially from a metal tube or barrel)
(notice that this definition does not include the word "propellant"
merriam-webster
1 a: a piece of ordnance usually with high muzzle velocity and comparatively flat trajectory b: a portable firearm (as a rifle or handgun)
c: a device that throws a projectile
Through deductive reasoning, one can conclude that all firearms are guns but not all guns are firearms...that is, unless you consider a glue gun, staple gun and pellet gun all "firearms". Ironically, neither of those guns use a propellant. In case you're wondering what a propellant is...
Propellant:
A low explosive composition, solid or liquid form, which burns and does not detonate. Propellants are used for propelling projectiles and rockets and to generate gases for powering auxiliary devices.
Green gas used for airsoft guns are not explosive. And as far as I know, most pellet guns use compressed air.
This begs the question, where are
you getting your definitions from?
edit:
Additionally, it's Alcohol Tobacco & Firearms, not Alcohol Tobacco & Guns.