So many, but the funniest has been "meme" (English is not my first language). My online friends who are English speakers were eternally amused by it, sadly my audhd brain has forgotten how I pronounced it.

While we're on the subject who the fuck decided lingerie should be pronounced lawn-jer-ay? Petition to stop letting the French decide how words are spelled because if I have to try to correctly spell burgiouisey one more time I'm going to flip.

All of them (technically)

I'm ESL

Paradigm. I pronounced it para-dig-m, like an idiot

Segue, how the fuck are you supposed to guess the pronounciation of that when there's hardly any other english words like it? I pretty much didn't learn the actual way to say it until university. I always said it "SEGG" and just assumed the rest was silent because it's ridiculous.

ennui, but really do french derived words count

Everyone in my elementary school pronounced zealot as zeal-lot.

Melee

I still say it wrong

Parable of the Sower... I thought it was a book about pigs (sows). I still mispronounce it in my head.😅

What is one word you realized you were pronouncing wrong until you heard someone else say it?

Mine: affidavit

Pronounced it a-fit-a-vit (not unlike "a Fitbit") for about 3 months in college trying to get out of a dorm contract I wasn't happy with.

Nitter

I'm dyslexic so my relationship to words like "affidavit" is a strange one. My first exposure to the word must have been via a tv series. I watched an insane amout of tv as a kid. So I heard the word many years before I ever saw the written form. With such words - there's confusion in my mind when I see the written form. If I were to look at the word and try to pronounce it - I'd likely mispronounce it like then I was a kid coping with pretty easy words that still gave me grief.

So many author's names

don’t have a good answer to OP’s question but i just want to give a shoutout to my fellow IPA literate sickos in this thread fighting the good fight

Death to America

Subpoena, pronounced it as sʌb-pəʊ-ena (/suhb-pou-ehna/). There is no argument that oe should make an [i] sound. I refuse to entertain the thought.

"Calliope". I thought it was "Kal-ee-ope". I found out like last week it's "Kal-I-Oh-Pee".

Ennui

Used to say it Enh-ooey

ptolemy. and ptolemy.

I used to pronounce respite as re spite.

Dachshund and indicted:

Dash-Hound In-Dicked-ed

Even though I heard people pronounce dachshund I didn't connect it to the written word until I was in my 30's probably. I knew that a weiner dog was a "doc-sun" but didn't know how it was spelled

Worcestershire sauce. If it was meant to be pronounced wooster why did you add the rce bit

Same goes for Leicester.

All of them. I read everything phonetically and then my brain jumbles it up for extra word flavor. I mispronounce words you can't even imagine

Ironically, shibboleth.

Took me way too long to realise that colonel is pronounced like kernel. Even while writing this very post I had to fact check it in the dictionary to make sure I'm not posting it wrong like a fool. Like, c'mon... there's THREE vowels in the word... three vowels three syllables! What the heck!