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What obvious adult discoveries made you feel a bit of a plonker?

687 replies

Airconfan · 21/09/2026 00:36

What’s something you learnt as an adult that made you think that’s completely obvious and yet I have never considered that….i feel like a bit of a plonker?

Mine was when taking tablets, the more you drink with it the better it will dissolve. I think alot of tablets are testing with the assumption people will drink 250ml alongside it.

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11
bongsuhan · 21/09/2026 09:59

Weekmindedfool · 21/09/2026 07:59

Well yes it does, by moving to shallower coast.

I believe the water stays put as the earth revolves, so it is not the water rising when the flood comes in and out but the technically the land moving in under the water "bulge".

PersephoneParlormaid · 21/09/2026 10:00

After years of storing onions and potatoes together in the garage, I’ve recently discovered that you shouldn’t, onions make the potatoes sprout sooner than they should.

KatyKan · 21/09/2026 10:00

Justforchristmas · 21/09/2026 07:20

Chimley is a regional variation of chimney

In some areas it has a B as well; chimbley

Thewonderfuldollypartonsbra · 21/09/2026 10:00

Not me,but my ex

He really thought we peed from our vaginas and asked 'why don't you women just clamp it shut while on your period?'

He genuinely couldn't understand why we used any form of san-pro

He didn't know what a cervix was and didn't 'get' the connection was between giving birth and a woman's milk kicking in

At the time,he was 34 and a father!

I had to give him a birds and bees talk and then he got his mother to finish us because I told him to pay for his dd who wasn't his bio dd but she had called him dad almost from birth

I asked if he'd paid any attention to sex ed at school and got grunted at

My (now adult) dd thought that if you gave a lad a blow job and actually blew,you could get pregnant

I did put her right (and explained how to give a bj!)

She was only 13 at the time and had read about it and got a bit confused (which was fine)

As a child,if you asked my mother where she was going,you'd get 'to hell and back to see how fair it is'

I thought she really was going to hell and was a teen when I worked out it meant 'keep your nose out'

I did not know that about rainbows-everydays a school day

NetZeroZealot · 21/09/2026 10:00

Bananavibez · 21/09/2026 03:19

That you dont rinse your mouth out after brushing your teeth

The dentist told me this years ago & I do try but always go back to rinsing!

Katiesaidthat · 21/09/2026 10:01

TheOwlShootAtNight · 21/09/2026 09:05

That would be some unsafe pool.

BTW being working class does not mean people are not intelligent.

Edited

She meant not wordly wise, or well travelled, nothing to do with intelligence.

sherbetlemonade · 21/09/2026 10:01

Releasemeplease · 21/09/2026 08:14

I'm in my 70s and I only learnt that last month!
I've brushed my teeth twice a day since a tiny child but I was never even shown how to use the toothbrush correctly. So my dental hygiene routine has been a learning curve all my life. The not rinsing came to light after the new hygienist I saw last month advised me to get a water flosser. When I bought it I was confused about where it fitted in to the tooth brushing, interdental brushes and mouth wash procedures. Google A1 provided me with a tooth cleaning regime which included the information about not rinsing after brushing and mouth wash should be used to freshen the mouth at mid day or similar tims in-between brushing. I'm still reeling from the shock.
Also fed up that tooth cleaning, boring at the best of times , is also now more complicated. On the plus side I've got all my own teeth and they are in decent nick.

But what are you supposed to do with all the froth?

StormInaDcup99 · 21/09/2026 10:03

Thewonderfuldollypartonsbra · 21/09/2026 10:00

Not me,but my ex

He really thought we peed from our vaginas and asked 'why don't you women just clamp it shut while on your period?'

He genuinely couldn't understand why we used any form of san-pro

He didn't know what a cervix was and didn't 'get' the connection was between giving birth and a woman's milk kicking in

At the time,he was 34 and a father!

I had to give him a birds and bees talk and then he got his mother to finish us because I told him to pay for his dd who wasn't his bio dd but she had called him dad almost from birth

I asked if he'd paid any attention to sex ed at school and got grunted at

My (now adult) dd thought that if you gave a lad a blow job and actually blew,you could get pregnant

I did put her right (and explained how to give a bj!)

She was only 13 at the time and had read about it and got a bit confused (which was fine)

As a child,if you asked my mother where she was going,you'd get 'to hell and back to see how fair it is'

I thought she really was going to hell and was a teen when I worked out it meant 'keep your nose out'

I did not know that about rainbows-everydays a school day

I only found out fairly recently that the term blow job is a shortened version of below job ie b'low job!

SugarMuffins · 21/09/2026 10:03

This is embarrassing but I never knew bed bugs were real till I was an adult and only a few years ago. I thought it was just something people said to scare kids.

NicNakNicola · 21/09/2026 10:04

I was an adult when I found out narwhals are real and not a mythical creature in the same category as fairies, mermaids and unicorns 😂

OneLivelyLion · 21/09/2026 10:05

That raisins are dehydrated grapes.

TheOwlShootAtNight · 21/09/2026 10:07

Katiesaidthat · 21/09/2026 10:01

She meant not wordly wise, or well travelled, nothing to do with intelligence.

You did not understand my answer.

Mulledjuice · 21/09/2026 10:08

Shedmistress · 21/09/2026 08:06

You don't even need to do that. A flash from an old fashioned camera should recharge them.

or - the sun?

Pudmyboy · 21/09/2026 10:08

stillhiding1990 · 21/09/2026 07:17

I’m not - I’m just puzzled. Where did they think the uterus came into it?

No, that is still shaming others. For instance, those people could think the uterus is at the top of the vagina and the urethra could be near the entrance of the vagina. You would be more honest just putting the laughing emoji, rather than this fake 'puzzlement'.

x2boys · 21/09/2026 10:09

TheLambtonWorm · 21/09/2026 09:22

Your fallopian tubes aren't connected to your ovaries and they just sort of use little finger like structures to waft / beacon the eggs in. What?!!

Slightly more embarrassing, birds don't sleep in nests. They just hatch eggs there and sleep on branches / in foliage or what have you.

Edited

Well i didnt know that i thought they all slept nice and cosy in their nest with their chicks
I blame a childhood picture book.

Theresmagicwheretheflowersgrow · 21/09/2026 10:10

montysmaw · 21/09/2026 09:23

i just found that out.......now!

And me. And I'm considerably older than 40!

drspouse · 21/09/2026 10:14

bongsuhan · 21/09/2026 09:59

I believe the water stays put as the earth revolves, so it is not the water rising when the flood comes in and out but the technically the land moving in under the water "bulge".

Edited

The tides are dependent on the moon, not the rotation of the earth.

Additup · 21/09/2026 10:14

About 5 years ago I discovered that if you cut a worm in half it doesn't make independent worms...apparently. I still don't really believe it tbh 😂

ChoccyHobknob · 21/09/2026 10:16

JudgeJ · 21/09/2026 09:39

I recall drinig through an industrial area and seeing a huge sign saying TOILET, I only realised later that the I was an addition.

Not discovered as quite an adult but when I was about 16 my mother commented that I had the knife in my left hand when peeling an apple! We realised that I always use my left hand for some tasks when I am generally right-handed, it's called cross dominence.

Oo is that what it is? I just thought I was "a bit" ambidextrous - I can play tennis or use chopsticks with both hands. But prefer my left for some things and right for others x

Isabella70 · 21/09/2026 10:17

I wonder how many people think that limes are unripe lemons? I saw an advertising campaign in a Belgian supermarket quite recently aimed at dispelling that (though it might be more understandable in French given that they are called citrons verts).

Mulledjuice · 21/09/2026 10:17

drspouse · 21/09/2026 10:14

The tides are dependent on the moon, not the rotation of the earth.

both, i think - the sun and the moon both exert a gravitational pull and the earth rotates into one and out of the other.

x2boys · 21/09/2026 10:17

BlondeFool · 21/09/2026 09:28

I thought the Falkland Islands were just past Scotland and I couldn’t understand why Argentina wanted them back.

I heard that was a common misconception at the time.

AbzMoz · 21/09/2026 10:19

When I first got my tortoise, I had a very long and confusing conversation with my mother who had evidently believed the cartoons and thought that the shell was detachable. She was scared of my holding up on a video call in case he slid right out…

SoupSoup · 21/09/2026 10:19

sherbetlemonade · 21/09/2026 10:01

But what are you supposed to do with all the froth?

How much froth is there? Are you wetting your toothbrush before applying toothpaste?

Becuriousnotjudgemental1980 · 21/09/2026 10:20

I thought Arkansas was pronounced ar-Kansas. I wondered where ar- kinsaw was on the map of the USA!!