what is the proper term for a magazine fed handgun like a glock, beretta or desert eagle?

Sometimes people use the term “automatic”, but it’s usually a sign of someone who isn’t real gun-savvy. In the gun world, people nearly always refer to that kind of pistol as a “semi-automatic” or “semi-auto”. I guess you might say it’s just proper etiquette when talking guns to specify “semi” or “fully” when using the term “automatic”.

An automatic. A revolver is called that because the cylinder revolves around to aline each cartridge with the firing pin. An automatic is fed by a spring loaded magazine when fired the recoil gases are chambered back to eject the spent cartridge and allow the live one to enter the firing chamber alining it with the firing pin. Winchester is a brand name not all rifles are Winchesters and not all Winchesters are rifles. Although most hand guns like the ones you mention are semi-automatic which means you have to pull the trigger every time to fire them some pistols are fully-automatic and you only need to pull the trigger once to empty all the rounds.

fire stick

We generally call it a Dopesgun. Or sometimes a "coqex-tender". Either way, small American boys seem to think it protects them from evil commies, and savage enwards. So I guess you could call it a pacifier.

An automatic. Because they are auto - loaded.