If the pilot announces, “we will be in the air momentarily,” it means you’re going to crash.
If the waiter assures you, “your food will be here momentarily,” it means you’d better eat fast.
If you are told “a customer service representative will be with you momentarily,” it means she won’t have much time to assist you.
If the theater manager says “doors will open momentarily,” you’d better hope you’re at the front of the line.
“Momentarily” means “for a moment” or “briefly,” not “in a moment” or “soon.” You may disagree, lots of people do—usually the ones who use it incorrectly or who quote a source that has just plain given up and added the erroneous definition.
I won’t be surprised by comments that cite sources accepting “in a moment” as an acceptable definition. It happens all the time. I once lost a bet with someone when I claimed “irregardless” wasn’t a word and that it couldn’t be found in the dictionary. I placed my bet, looked it up and there it was: “irregardless: an incorrect use of regardless.” As with “sherbert,” some sources have just shrugged their shoulders and looked the other way.
But I am fair and have an open mind. If you do disagree with me, feel free to state your case. I will listen to you momentarily.
Word Nymph 
I knew I would be entertained. I hoped not to recognize myself in some of the stories. And while I am not always the sharpest crayon in the box (credit: Uncle Gerry), I soon will be!
Now, when will you tackle “And what not” and “It is what it is”? And don’t try to fool me with momentarily!
I will enjoy this beyond a moment!
Dave would tell you this is an ongoing irritant for me!
Now let’s discuss “hopefully.” I can remember a story from the ’70s involving (if memory serves, and it rarely does these days) an OED editor who had a sign on his desk that read, “Anyone misusing the word ‘hopefully’ will be publicly humiliated.”
Sister Bernadette,
Starting each morning with wordnymph is not only amusing…it’s educational. When you- prose master extraordinaire, validate the correct use of grammar; I’m either emboldened or blush by your post. Recently I’ve had little use for my bare minerals- aubergine.