This one drove me crazy for years until I just gave up. ‘Quantum leap’ seems to be used to describe a descrete, revolutionary change rather than the normal gradual changes we are used to, and that is sort of correct. But to me phrase means the smallest change possible. At quantum levels things don’t change gradually, they leap from one state to the next so a quantum leap is as infinitesimal a change as there can possible be. Maybe I haven’t given up on this one.
I understood “quantum leap” to indicate when something goes from state A to state B, skipping the (assumed) intermediary steps. It is the non-linearity that makes it a quantum leap forward, and not just a strong advance.
That’s been my interpretation of “proper usage” of the term. Physics classes helped me relate to it more than just common parlance and that’s true of so many things the general public accepts at face value and distorts out of the original intent. We could explore those things in a separate thread if somebody wants to jump off and start one. 
I agree with the above. Think of it like this:
A quantum is something that is unsplitable, not made of smaller parts.
A quantum leap is a change that happens instantly, in the smallest possible unit of time.
And the little star thingy above the 8 (on a US keyboard) is called an asterisk. Not an asterix.
Don’t even get me started on people who use loose when they mean lose. Drives me absolutely bonkers.
Yeah, ‘quantum’ and ‘quantum’ leap are two different things, as their M-W entries attest.
Nitpicking this (hyperselective literalism?) is about like saying “breakneck” speed is a misnomer because you’re not actually breaking your neck.
To bring up another one that bugs me, though, akin to quantum, I’ve lost the battle on this one (probably before my birth, but so what?):
There is a letter called “Oh”. There is a number called “zero”. They look a lot alike, but are not the same thing. So please, Sprint (for example), when I dial a number that is non-existent do not say “The number you have dialed, ‘two-one-oh-five-five…’!”
I do not say “My user name is spelled ‘Jay-zero-aich-enn-tee’.” Why? Because a “O” is not a “0” and to spell it out that way is freakin’ idiotic. So, please, for the love of God and all that is Holy, don’t tell me that zero is oh.
Thank you. You may return to your regularly scheduled thread. 
I didn’t know this. I always thought escalate meant to raise something up. You could escalate a problem by raising its level of difficulty or escalate a fight by raising its level of violence.
But I also figured an escalator raises people up from one floor to another - it doesn’t make its passengers more intense. So while I never used escalate to mean telling something to a boss, I could see the sense of it - I figured you were raising the issue to the next level of management.
So what is an escalator supposed to be intensifying?
Well, as long as you don’t escalate the problem to your direct reports, you’ll probably be OK. However, if the problem is large enough, you’d best escalate it to the responsible C-level and let them deal with it.
My peeve is Commander and Chief. Please. Make. It. Stop.
Around here, I hear asterick more often. I have a memory aid (I’m never sure how mnemonic is spelled) for that. “I regret that I have but one asterisk {*} for my country.”
I don’t use quantum, because I don’t understand that branch of physics. I avoid using the French words I know, because I probably don’t say them right.
Actually, I think decimation was a punishment meted out to a group of soldiers that had underperformed - the Romans were actually killing 1 tenth of their own guys as an example to the remaining 9.
Here’s a handy way to remember the spelling of mnemonic:
Mexicans Never Eat Menudo Outdoors Near Impertinent Cholas.
Damn that Uderzo and Goscinny pair…
Growing up the teacher/student back-and-forth was always:
“Can I go to the nurse? I don’t feel good”
“No Jimmy, it’s I don’t feel well”
It took me until the middle of college before I realized that it’s correct in saying “I don’t feel good” because putting in “well” makes it seem like you’ve lost ability to feel things with you hands and such
The word, ‘niggardly,’ has nothing to do with racism.
Plus, the possibility of getting into the business of “you can go to the nurse, Jimmy – the question is, whether you may”… It could come to seem that the whole pedantry / precise-definitions thing, was going in the direction in which madness lies.
Now all we need is a mnemonic to remember that phrase.
Just remember that each word in that phrase starts with the next letter in the word “mnemonic.”
Correction: From Uncle Tom’s Cabin.
“Have you ever heard anything about God, Topsy?”
The child looked bewildered, but grinned as usual.
“Do you know who made you?”
“Nobody, as I knows on,” said the child, with a short laugh.
The idea appeared to amuse her considerably; for her eyes twinkled, and she added, “I spect I grow’d. Don’t think nobody never made me.”