Oh! And there’s the time in high school I was asked to read a short passge aloud in bology class and I read, “orgasm” every time I saw the word “organism”…
Not my fault. Stacy Meyers Parkerson wasn’t wearing a bra, right by the air conditioner.
I think a good example of mass mispronunciation is the flower name Fuchsia, which I’ve always heard pronounced as “few-shi-a”.
Fuchsia was named after a German named Fuchs, which is pronounced “fooks”. So Fuchsia should be pronounced “fooksia”, but I think people were afraid to pronounce it that way because it vaguely like “f***sia.”
Or maybe not.
ironical 
cow-orker
pedanticism
I’m surprised nobody pronounces it whores de ovaries. Maybe that’s too wrong even for a plate full of stuffed green olives.
This isn’t quite in the same category, but I routinely tell people to make sure all the Is are crossed and all the Ts are dotted. I say it with a straight face and nobody ever questions it.
When I’m around my siblings, we say “sammidge” for sandwich, and “brudder” or “bubber” for brother. I like to say “pum pum” (pumpkin) and “zee-buh-buh” (zebra) because my niece said them that way when she was little and cute.
My friends and I say ‘bohemic’ instead of ‘bulimic’ A friend of mine thought one of the girls in our grade was bulimic and she said bohemic. The word doesn’t come up much, but when it does, it will earn laughing spasms from my friends and I for quite a while.
When my nephew was little he’d say something was eeeeeeelicious when it was yummy. So my husband still says it. I call feet, feeties. The singular is footy. My son has outgrown it, but I can’t stop myself.
Oh, that’s right—the plural of “fish” is always foosh.
Oakland’s shortstop is, of course, Miguel Tostada.
There’s always LMAO. I have never had to say it out loud, just in my head, where I hear it like “lmao.” Yep, like “lumaoh.” LOL is, of course, “lol.”
I say it like that sometimes. It’s because someone on the show “My Wife and Kids” (Junior I think) pronounced it like that and I thought it was funny.
I always say “prolly” for probably, but I’m a naturally fast talker anyhow and a lot of my words get jumbled or mooshed when I talk.
I work at a mexican restaurant and I always say “grassy-ass” insterad of gracias and “de nuda” instead of de nada. It just sounds funnier. I also pronounce jalapeno like jap-a-leen-yo.
My dad has owned a number of Porsche automobiles over the years, and he and I both say “Porsh.” This is an affectionate shortening; we know the word actually has two syllables. But many people think it really is “Porsh.” I’d hate to be mistaken for one of those but I guess I frequently am.
All fashion copywriters say “fucksia” softly to themselves, by the way. It’s the only way to spell “fuchsia” properly without looking it up.
At the keyboard, shift your right hand one key to the left. Then type the word “lesbian” and you get “kesbuab.” Discovered this years ago; ever since, all girls-who-like-girls are kesbuabs to me.
Mine are “prolly,” “sammitch,” and “veggimles.” As in, you could prolly chop the veggimles for the salad while I make the sammitches.
My 14 year old cousin somehow had the idea that “infomercials” were actually called “nymphomercials.” We set her straight, but the phrase “nymphomercials” stuck.
Whenever my family plays Clue, the revolver is always referred to as the lualua (say revolver with a really bad Chinese accent. Get it?). No idea when or why this started.
meelee.
it just sounds better that way.
bones - spareribs
trees - broccoli
bumbershoot - umbrella
froggy - foggy
(all obvious and dull) 
effelump - elephant
murky buckets - merci beaucoup
bissketti - spaghetti
hanguber - hamburger
If I had a heckalopter I’d fly it to Grass Pants (Grant’s Pass, OR).
I pronounce Oregon “Or-eh-gone” as opposed to the “correct” pronunciation (something like “Organ”) because I’m a stubborn asshole and think that I’m right and everyone who lives in that state is wrong.
That was my sister’s pronunciation too.
That’s not a valid pronunciation? I never knew.
I always say “not nessi-celery”, got it from Benny Hill I believe.
Sammitch - From Tom Servo’s “Mitchell” song
All French words are spoken phonetically. A woman was telling me about a house she was looking at and mentioned the “Fwa-yea”. Toots, that’s a “foy-er”. Appetizers are “horse ovaries”.