I got a lot of words wrong. If I read about someone being truculent, I heard it to myself as “truce-a-lent” until I heard somebody say, “truck-ulent.” Oh, okay. Pretty much the same with lugubrious, and it was the same person who said it.*
I would have pronounced “renege” as “ree-nezh” and not related it to the word we used when playing cards, except I ran into it in a bridge book. Oh…
There are tons of words like that. I have a huge vocabulary when writing, but frankly I’m afraid of mispronouncing a lot of those words so I never use them in conversation. They don’t even have to be big words. I’m quite capable of screwing up a very small and easy word when talking. Like “spa,” no it’s not what you do to your cat.**
*I think I looked them up to make sure he was pronouncing them right. At any rate he was very confident in his pronunciation.
**A coworker and I once developed the concept of a cat spa. You get a cat, and spend a day doing just what the cat does. 8-10 nap. 10-11 groom yourself–do your nails or something. 11-11:15 have a little snack. 11:15-3 nap. And so on. At some point go find somebody and force them to give you a massage. But I digress. The point is I had to really concentrate to call it “catspaw” instead of, well, you know. The other thing. And this was at work, where I was an editor, so I really didn’t want to appear ignorant.