Table might count for me here.

I grew up in America and "a bill was tabled" means that a bill was removed from consideration there... while as in Canada it means the precise opposite "a bill was tabled" means it was introduced for debate.

I don't use the term often in common speech, but I was really confused reading political news when I first arrived.

Encephalitis is caused by viral infections. Our immune system usually suppresses said viruses, and HIV takes away the ability to suppress them.

This happens with a lot of illnesses... thrush, Tuberculosis, fungal infections. HIV allows a lot of stuff to have far worse impact than it normally would.

That's not quite the same as HIV causing them... Pedantic maybe, but since we're talking about words meaning things... ;)

every word i use is right, its the english language that is wrong

I was homeschooled and was basically educated by books, so I have a massively large vocabulary and I mostly use it correctly.

But pronunciation? I'm fucked.

Oh in English -- I used to say renumerate (numerate a second time) instead of remunerate (pay someone for a thing).

How about " till " in English vs " 'til " ?

In English, a till is a cash drawer or a plough. The abbreviation for "until" is " 'til ".

I see it in subtitles. I worry for society.

I used the term 'pursuant' incorrectly for a long time. I thought it meant something like 'things you do in order to achieve something', like sweeping the floor is pursuant to getting the kitchen clean, vs the correct usage, which is either 'in accordance with', or 'in a manner conformable to'. So a correct usage would be 'sweeping the floor is pursuant to the procedure we set up to clean the kitchen'. Nice word, though. I like it.

Freedom.

Apparently where I live it means torture people till they off themselves.

I thought penultimate meant ...basically ultimate

Am doofus

Edit: to clarify, I thought it meant it in a good way, as in best. It actually means next to last

I thought phallic (fálico) meant flawed (falho) and used it so much. I cringe when I remember this 😭

Awkward because encephalitis is caused by HIV.

From the NHS website:

Encephalitis is most often due to a virus, such as:

• herpes simplex viruses, which cause cold sores (this is the most common cause of encephalitis)
• the varicella zoster virus, which causes chickenpox and shingles
• measles, mumps and rubella viruses
• viruses spread by animals, such as tick-borne encephalitis, Japanese encephalitis, rabies (and possibly Zika virus)

Encephalitis caused by a virus is known as "viral encephalitis". In rare cases, encephalitis is caused by bacteria, fungi or parasites.

I didn't realize "effect" and "affect" were different words for a long time.

literally, apparently.

Is encephalitis caused only by HIV, though?

I seem to think it was a thing before HIV.

I used poignant wrong for a long time, when it came to describing memories. I thought it meant the memories were strong, clear sensory ones but it meant sad ones.

I thought "long COVID" meant "lung COVID" because in dutch long = lung

Nothing too big or embarrassing, but for a while I thought "nepotism" just meant the same as "narcissism" when it's actually about favoritism towards one's family.

I happily described a nice coffee shop as "kitschy" to the guy behind the counter and quickly learned from his reaction that it isn't the synonym for "artsy" that I thought it was.

For decades I pronounced albeit like "al-bayt", instead of "all-be-it". I only ever saw it in writing, and never hears anyone say it. Meaning made also so much more sense when I finally heard it being said out loud. Eye opener.

Not a super long time but I conflated apocryphal with like sagely or scholarly

Can I submit an expression? "Have the work cut out for you". My thinking was "there was a lot of work, but my boss said I'll have the work cut out for me. Phew, now there's less work after some of it being cut out!"

I used to say "worth nothing" while, obviously, the correct way is "worth noting".

However, given how many Google results are there about the wrong spelling, I'm clearly not the only one.

When I was a kid, it was Yosemite.

I was obsessed with GTA San Andreas, and that was the big truck in the game, and it was my favorite. I was pronouncing it like "yosa might" for a while until somebody pointed it out, and then I connected the dots

I lived for the better part of a decade in Vietnam thinking "đại lý" was a loan word from English meaning "daily".

It actually indicates an agent (like a reseller) -- e.g. a lottery ticket seller, news stand, and so on. "Daily" just worked in all those contexts by coincidence.

I also mix up "in stock" (in a warehouse) and "available". So an analogy is I often ask people if they have "a clock in their warehouse" instead of if they "have the time".

Also probably two dozen equally weird things I'm not even aware of. People are pretty chill about it, mostly because the number of people without Vietnamese heritage that speak the language in any capacity, rounds down to zero.

I don't use it wrong because I don't use it but to me "mirth" feels like it has a negative connotation even though I know it means joyful.

Turns out pseudo is not spelled like sudo.

The word Segue meaning transition.

Always used Segway instead which was incorrect.

Nonce. I've always used it just like Dunce. Turns out it does in fact not mean the same and instead means pedo.

Encephalitis (en-sef-uh-LIE-tis) is inflammation of the brain. There are several causes, including viral infection, autoimmune inflammation, bacterial infection, insect bites and others. 

I don't use it very often but I misuse the word "Gattaca" on purpose sometimes. In reality it's the title of the 1997 film that's named from the letters G,A,T, and C, referring to guanine, adenin, thymine and cytosine, the four nucleobases of DNA.

But on the TV show The League, the character Rafi (Jason Mantzoukas) screams it as his battle cry during paintball, completely oblivious to what it actually means or that it's the title of a movie. I urge you all to misuse this word at some point as well -- if you ever need to hype yourself up, try screaming "GATTACA!" as your battle cry!

"Sorry."

In German we use the English term 'understatement' in some occasions, e.g. 'his dressing style is a clear understatement...'. My brain somehow tied the meaning to something like 'understanding', maybe due to the similarities of both words. For decades it was clear to me that someone dressing like that were dressed to the point and 'making a clear statement'. Now that I've checked the real meaning, I'm completely puzzled when and how to use the term and what I've misinterpreted all the years...

Since OP is in the UK, I can pull out “nonplussed.” Current American usage of the word is a lack of surprise or general acceptance. I am nonplussed when news arrives that another politician was caught in a sex scandal. Non-American usage is complete surprise and an inability to act. The Scot was nonplussed when the drunk American vomited noisily on his shoes.

Edit: I am firmly in the “general acceptance” camp and usually have to process for a second or two when someone uses it in its traditional sense.

When I was younger I thought concur meant disagree.

Man, I'm learning some weird stuff about British people. I've never heard of encephalitis being associated with HIV or a nonce being any kind of person.

Callow. It just means immature but I somehow got it in my head that it meant cowardly.

Not a word but I thought the idiom toe the line meant basically the same as push the envelope. As in you're testing the boundaries of something by walking right up to the line and nudging it with your toe to move it further.

Turns out it means pretty much the opposite, essentially the same as fall in line.

It took me until graduate school to learn that "mortified" is not another word for "scared"/"fearful"

It still looks that way to me what with mort in there!

It also took me a long time to realize that the word "awry", which I read often in books and inferred its meaning, and "ah-rai" were the same thing. I thought awry was pronounced "aw-ree" and it was just a synonym for "ah-rai".

Terrence Thatcher, T. May, Terroris, Ttruss;
Terry-Tories, Terry-Tories, make a fuss!

It also gives a different meaning to the citizens of British Overseas Tories!

Portuguese ⟨bisonho⟩. I always used it as "needy", "demanding excessive attention" (like a child). Until someone informed me that it was supposed to be "weird".

I mean, homonyms exist, confusing them/not knowing a word has one doesn't make it "wrong". Surely you (e: plural, not having a go at you op lol) could tell tories and Tories apart by context (if not capitalisation)?

Inconceivable!

Redux. I've always just used it as a fancier 're-do'. Still going to keep using it as such. I like the word too much.

Depreciate.

I'm going to Depreciate this computer. That means to get its loss of value on taxes....not to shut it down. The word I meant was Deprecate

With English as my second language, the difference between terrible and terrific has always confused me.

"Alternately" when I meant "alternatively".

"just" was meant to indicate a recent position in time. As in "just now."

The word "nauseous" is parallel to "noxious" and means "causing nausea". If you're experiencing nausea, you're nauseated -- the thing that made you nauseated is nauseous.

I have cryptolalia; so probably all of them.

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