I don’t think a .22 is considered a “pellet”
There are .22 pellet rifles, air powered.
“I don’t think a .22 is considered a “pellet””
I have a .22 pellet rifle.

.22 pellet guns exist. They’re fairly rare but they’re out there. They make one in .45 that can easily kill a deer
In these United States, air rifles are commonly sold in .177 and .22 caliber. Air rifles in .25 caliber also exist but are much rarer. Regardless of caliber, air rifle projectiles are generally referred to as pellets.
Take a look at the air rifle section on, for example, the Cabela's website. Modern air rifles have come a long way from that Red Ryder BB gun you played with eons ago.
I have several .22 and .25 caliber PCP (pre-charged pneumatic) pellet guns. The .25 is equivalent (muzzle energy) to a .22LR. There are pellet guns up to about .50 cal.
But it is a caliber....
There are .22 caliber pellets. Google it.
It is if it's shot from a pellet rifle. See my home page.
You have. .22 cal pellets shot from pellet rifles and .22 cal rimfire cartridges shot from firearms.
https://www.airgunnation.com/threads/crosman-600.1235230/
https://airgunwarriors.com/community/airgun-talk/crosman-m-600/
I have a fine little pellet gun collection.
My favorites are my Crosman 600 pistols.
They are .22 and are quite accurate and hard hitting!
I think your comment struck a nerve.
In addition to regular air rifles, all the cool kids are using the for international shooting, including the Olympics. Some of them cost more than $4k.

With a pellet gun like our Gamo Vermonters you can shoot regular pellets then there’s A raptor pellet that does a lot more damage and its going at the fps of a .22. We have killed large possums with ours that were trying to get in the chicken coop.
Think they meant 22 cal air rifle. It’s a popular size.
There are .22 pellets.
Pellet guns come in .17 and .22 caliber.
In an air gun, that’s what they call it because it is just a pellet, no cartridge.

That's without getting into Dennis Quackenbush,* who builds air rifles up to .50-cal, and which have been used to take American buffalo, black bear and African plains game.
http://www.quackenbushairguns.com/index.htm
* No, he didn't get his name from a Groucho Marx character. In fact he is distant relation to H.M. Quackenbush, who built airguns in the late 19th and early 20th Centuries.
https://en.wikipedia.org/wiki/Henry_Quackenbush
I have a .22 cal. pellet rifle, a U.S.-made Benjamin Marauder. It has slightly less power than a .22 Short round, with a muzzle velocity of about 850-900 feet per second and a projectile weight of about 20 grains. Small but potentially deadly... you should be just as careful with airguns as you would with a firearm.