“Blackguard” - shows up a lot in old comic books.
Nike was the ancient Greek goddess of victory, and her name was pronounced Nikey or Nikay (nǐː.kɛː). But it sure looks like it rhymes with Mike.
Pone.
One I mentioned in a similar thread: I was familiar with the written word ‘segue’, and knew its meaning as ‘a transition from one thing to another’. But I did not know its proper pronunciation. If you asked me, I probably would have said ‘soog’ or ‘seg-yew’.
I was also familiar with the spoken word pronounced ‘segway’. and also knew its meaning as ‘a transition from one thing to another’.
But, though it may seem obvious, I was well into my adulthood when I finally learned the word ‘segue’ is pronounced ‘segway’ and is one and the same as the word I had heard pronounced. It didn’t help my confusion that the scooter brand name was phonetically spelled ‘Segway’.
Yes, that’s it.
That’s the origin, then it came to jokingly mean “super-owned” and I’ve heard people (and used it) in speech as “Powned” (phoned with a p- sound, no h). It’s nothing I’d expect to hear outside the context of playing a game with friends and saying “hah, get pwned”.
For years I pronounced turmeric as ‘ter-MARE-ic’ before finally learning it’s ‘TER-mer-ic’.
Mrs. Solost pronounces it ‘TOO-mer-ic’, which is closer than how I used to pronounce it.
Oh for criminy’s sake, it’s gotta be ‘seg-yew’, surely?!? 
TIL - in my mid 60’s.
j
Huh. I’ve always pronounced it LYE-Lock.
I heard the word “duodenum” on Jeopardy once. So I saw it spelled and pronounced. Imagine my surprise when they said “doo-oh-DEE-num” instead of “doo-AH-den-um.” I’ve told the story of my giving a told-in-front-of-the-class report on the poem The Ancient Ma-REEN-er. I’m still traumatized…
There must be hundreds of such words but I can only think of one offhand. On an episode of Picket Fences I saw recently, one of the characters pronounced certiorari (an act of a court granting an appeal, pronounced something like “sir-she-a-RAH-ree”) and I realized I’d never heard it pronounced before.
I’ve heard ecru pronounced before in the context of needlework (it’s a common color of embroidery floss). I’ve heard etui pronounced before, but only on Jeopardy!.
Ok, that I’ve heard as well. Lack is apparectly correct but I wouldn’t pause (or correct) someone saying “Lock”
I often have the opposite problem. I listen to tons of audiobooks, and have had cases where I’ve only heard the word. When I see it in print it takes a minute to realize I know that word (chimera would be a good example).
On MASH, Colonel Potter pronounced it as “doo-AH-den-um.” I trust Sherm Potter over either Alex Trebek or Ken Jennings.
I have found just now there are both pronunciations out in the wild! I love not being wrong. And I agree, Colonel Potter was a very smart man.
How about Weird Al?
(2:34)
The town of Greenwich NJ is pronounced “green witch.” So there you go!
Back in the day of it being a very popular powdered fruit juice mix, we used it a lot.
Both used in role playing games, but not in reality.
The Brit mispronounce a lot of geographic names. Of course, after centuries, I guess those mispronunciations are now the correct one. Cholmondeley is said as “chum-lee”! 
There is no way you can get these from the spelling.
Not if you read news about Russia.
Since marine biologists pronounce it as “octopuses” , you were both wrong.
Well, sunovabitch. I’ve always pronounced it DET-rih-tus, like you. Like a poster above, I’ve also pronounced “chimera” as “CHIM-uh-ruh” not “ky-MEER-uh”. I also was surprised when I first heard “simulacrum” in conversation for the first time. I’ve always said it “sih-MULE-uh-crum” (or thereabouts) to myself; turns out it’s more like “sih-myuh-LACK-rum.” Also, as a kid, I said “oh-reh-GAH-no” for “oregano” and was somewhat vindicated when I visited across the pond (the US says “oh-REH-guh-no”).