Underwear

Knickers!
(My OH pointed out that for some reason I always refer to them as "me knickers" rather than "my Knickers"! I hadn't noticed that I did that!)
My dad used to refer to what we call the loo as "the little boys' room" - which in their home was the one with the shower in it as opposed to the one with the bath in it which my mother used.
Our "special" euphemism is "going for a sudoku" from when we always had a book (now a tablet or phone) to while away the time as I often get constipated.
..and bras - at school we called them "over-shoulder-boulder-holders". (Not that I had any boulders, just pebbles!)

I like undercrackers. 🤭

When young always used "going to the bathroom" for the toilet as that was in the bathroom. I was often reminded the toilet is the lavatory! Now it's the toilet or loo or even bog. Some places have for quite a while had washroom on doors instead of toilets. Nowadays I don't care what tgey are called as long as clean, with toilet paper and hand washing/drying facilties.

My view:

Lingerie = underwear and covers all undergarments (although if you look at our female pop stars these days they are anything BUT under)
Knickers are smaller frillier versions of pants, except for small children, where pants will do as simpler
Trousers are only pants in North American continent

Bathroom is often now more accurate because the bath is often in the same room as a toilet, but my mum would "spend a penny" and my dad would refer to "the little boys room" <lol> Toilet being a derivation of the French "toilette" which I believe covered washing too. Lavatory is also French as a place to wash. We have WC on some public spaces (water closet), but being lazy it has always been loo for me

NanKate

I remember people saying ‘the Lav’ which I thought sounded awful.

The lavvie was a favourite too for men.

Bra & knickers for me. Never worn a petticoat in my life.

I always understood Napkin to be cloth and serviette to be paper, Grantanow.
We have napkins at home.
I didn't realise a serviette could be cloth - though it would potentially be fabric in France where I think it's a "serviette de table".

Agreed Nancat

At school, and I think that Boadicea and I went to the same boarding school (apologies if I’m wrong) the loo was always called “the ever” because we were “forever going”. The nightly call by matron was
“ if anyone wants to go to the ever, go now because it’s lights out”
Forever etched into my brain!

Notagranny44

I think that the men's knee-length trousers that are worn now for shooting and for casual wear by men before the war are usually called "plus-Fours" in the UK. Knickers is an Americanism I think. The "plus-four" refers to the addition of four inches of length added to the measurement of the waist to knee when the are being made, so you can bend your knee easily when wearing them.
You can also have "plus-sixes" and "plus-eights" giving a baggier look. My Dad had a pair in his youth.

Knickerbocker Glories😃

The queen always said lavatory which is the correct name

If she had visited my house, she'd have used the toilet, the same as everyone else

That made me laugh!

My mother always said lavatory so when I was a stroppy teen I said toilet just to wind her up. Now it's the loo.
I wear knickers my sons wear boxers. Small children wear pants.

My neighbour told of the whole family sitting down ready for Sunday dinner.
Her dad asked where Peter was, and some bright spark said "He's on the bog!"

She said there was a deafening silence, and her dad asked bright spark to repeat what they'd just said.

When they did, Dad dragged them away from the table, and chased them upstairs, ranting about "profanity" at the dinner table!

i have always said knickers, it used to be high waisted always black, now due to having to wear pull up pants all the time i buy the ladies boxer type knickers from temu, they are made from 90% Nylon, 10% Elastane, so they are stretchy and comfortable and cover all the pull ups. i have always said loo and boobs.

Mam said she was off to the netty. Toilet in north east of the uk.

MrJ calls his boxers cacks. We say toilet or loo.

He’s Irish..

My grandmother called my brothers’ shorts ‘knickers’ and called our long school socks ‘stockings’ to our absolute disgust.

Hate the words knickers,panties,loo, lav, wc I like the words bathroom,toilet,underwear,pants

I have just been doing a bit of googling and confirmed my own suspicions that there is not a single word in the English language for the room we go into to void our human waste that is not a euphemism.

bathroom, washroom, latrine, loo, water closet, cloakroom, bog, comfort station, john, convenience, commode, heads, privy, garderobe, powder room, ladies, wc, lav, netty.

I have just found one: urinal, but that is specific to one form of waste not the more general.

Not sure what happens in other languages.