In my reading I frequently see words that I never hear actually spoken in conversation. Here are four I saw just this morning.
atavistic
alacrity
soubriquet
inveterate
Does anyone actually use those words in speech?
Does anyone have a favorite (favourite) they use in conversation just to throw people off?
I’ve used alacrity. Not the others.
What always trips me up are the words that I “know” because I encounter them frequently in written form, and then, unexpectedly, I need to pronounce one and realize I’ve never heard it spoken that I can recall.
The last one I can think of is “nascent.”
(btw, pronounced NAY-sent, or NA-sent.)
Yeah. That’s a great word. I had the same problem with soubriquet.
Another is “cacophony”. I’ve used that one quite a bit.
I’m waiting for the opportunity to use “defenestrate”.
I was trying to figure out what verse had to do with this, and I finally figured it out.
If it’s pronounced “caca phony” does that make it a synonym of shampoo?
Hey, those are just regular words. I use them all the time. Except “sobriquet”, which I can’t work out how to pronounce. I’ve never heard it, even on Radio or TV.
But tell me, do people ever actually say “segue”? How do you pronounce it? Do they ever say “Copacetic”? (I’ve seen it written in Uncle Remus!)
Here in Yurp we’re wondering… does anyone really say “mosey”?
I’ve said all of those words…
“seg-way” (just like the two wheeled abomination)
And in texas, lots of folks say mosey (and "folks’) 
ca-CA-phony
So-brih-KAY
Co-pah-SETic
::waiting for Scottielvr to show up and correct me…it’s ok,it’s ok::
I’ve always heard sobriquet pronounced SO-brik-ett.
djm
Ca-cough-onee..well thats with a Dublin accent,of course.
I like to throw “Katabatic” into the conversation when I get the chance 
Slan,
D.
Defenestrate is my second-favorite word. Next to callipygian.
Look it up. 
In one of my politics classes, the professor uses the word hegemony/hegemonic a lot. Other than that, I rarely see it spoken because generally people don’t know how to say it.
I know the perfect example of that.
I use 1, 2 and 4 when the opportunity presents itself. They are more economical than any alternatives I can think of off hand.
No mater how many times I see it infrared looks strange to me.
You have done me a great service, sir.
Misled, too.
My favorite quintessential word is lagniappe (lahn-yop). It means a small gift or, more broadly, an unintended positive consequence. I used it in a paper once, but the referree and editor made us take it out and replace one word (which admittedly few people know) with three.
I’ll add mondegreen to the list. I never knew that word until this very day.
Hehe. I’m not much on pronouncements. I’ve been known to put the emPHAsis on the wrong syLLAble…a lot. And I went most of my life mispronouncing “forte”. And let’s not even mention “flaccid.”
I meant it about flaccid! Don’t even go there!
Hutchinson Dictionary of Difficult Words
I’m still trying to find a way to work “incarnadine” into a conversation as a verb. The problem is that it needs a noble setting, as in “the multitudinous seas incarnadine,” and those kind of situations just don’t come up every day.
Your assignment – use “callipygian” and “incarnadine” in the same sentence. For extra credit, work in “crapulous.”
Edited to fix spelling.
“gonzo’s orthopterous mug blushed incarnadine as he realized he’d misspelled ‘callipygian’.”
(P.S. Don’t want to verb incarnadine, and you can’t make me).