This happened to me.... The word was hyperbole. I said it as hyper bowl ee.
The kicker is I've heard the word hyperbole before, pronounced correctly, and never knew what it meant, nor how it was spelled.
So I spoke to someone who was a bit more linguistically inclined, both verbally and written (hes also older than me by a few years, and more "into" art and culture)... And he said "you mean hyperbole?" And everything finally clicked. At the time I was embarrassed because I knew both the written and pronounced versions of it, but never put them together, so I felt like it was something I should have been able to figure out on my own and didn't.
Now? If someone made the same correction to something similar, I'd be like. Ohhhhhh. That makes more sense. Thanks! Instead, I basically exited the situation to go die in private from embarrassment.
I'm kinda the same here, except worse. I'm stuck saying Hyper-Bowl, and the "proper" pronunciation breakes down as hyperbally in my head. Sounding like an adverb trips me up so much, I just refuse to use the word now.
Mine was Ganymede. I read so much scifi but didn't really ever see any scifi shows referencing the planet, and it never came up in conversation.
I thought it was supposed to be pronounced gani-mee-dee, as if it was a Greek philosopher.