Television became “TV.”
Air conditioner became “AC.”
Refrigerator became “fridge.”
To microwave is “zap,” but the appliance itself has no commonly accepted nickname or abbreviation.
Why not?
I’ve heard it called both a “mike” and a “nuker.” The former is much more prevalent, IME.
Whenever an initialization would include “W” it’s usually easier to say the original word. That doesn’t explain other possible abbreviations, though.
No one uses “micro” where you’re from?
I’ve heard “put it in the micro” plenty of times…
Microwave is itself a nickname. The full name is microwave oven.
Nuker is what I’ve always called it. I know it’s not really nukin’ but its fun to talk about nukin’ foodstuff.
I’ve always called it a nuker, too… The verb is “to nuke”
Okay, “nuke” is as common as “zap” for the verb – I’ve never heard it called either a nuker or a zapper, though. Esp. since “zapper” is a remote control.
Never heard it called a mike, though that makes sense. Or a micro.
I usually hear “clicker” for remote control, thus leaving “zapper” available for a microwave.
Never a “nuker”. Always a “nuke”
“Micro” is fairly popular in spanish, but that is not what you are asking.
Mike is common here.
Mike and micro are obvious, no?
Never heard “micro” or “mike.” We do, however, nuke food in the nuker.
Or sometimes, and just for fun, the “nukerator.” 
For me, a “clicker” is a remote control. A “zapper” is a blueish light that kills bugs. A microwave is just a microwave
No, actually “fridge” comes from Frigidaire, a brand name for one manufacturer’s refrigerators.
Maybe, maybe not – but the fact of the matter is there’s a one-syllable nickname for the appliance.
Nobody else pops it in the 'wave?
I will go one further,
I have been known to put “Microwave Dinners” down on my shopping list as simply
“Nukers”
Hey. I’m College aged.
Ok, I’m 25, and I graduate in Decemeber.
Nuker is what we use to called it. I haven’t heard that for quite some time though. I figured it fell out of use.
Are remotes still commonly called clickers? That use to be common, but it is not like they click any more.
Jim
“Mike” baffles me, because “mike” = microphone. If someone told me to pop the leftovers in the mike, I would be totally lost.
I nuke foods that I put in the microwave, but calling it a “nuker” feels weird to me. Just can’t do it. I either say “microwave” (as in, “Put it in the microwave” or “Microwave it”) or “nuke it.”