Second forum - same question

Don't worry: you're right. You can expect a duvet instead of sheet and blanket.

I rather believe that they are referring to the duvet, which they
provide instead of a top sheet.

Yes, they're very likely talking about duvets and their enveloping cover sheets being provided but not the separate top sheets which most of us Americans are used to. Some folks find duvets too warm, especially in the summer months, but like to have a light covering over them. In that case, I've seen suggestions to ask housekeeping if they can provided a separate duvet cover to use as a sheet, or just to separate the duvet from the cover.

Simply -- same answer as to your first question -- no top sheet. Don't like it but it is common. Second, have also encountered this practice in the US. Not sure what is gained by not using a top sheet.

Or you could ask the hotels directly to know exactly what they mean.

Could you paste the links or at least copy-paste the actual text you are referring to from a couple of examples, so that we can see for ourselves?
I am easily confused by hotel room jargon in American English let alone other languages and translations therefrom. Often reading the original makes things clearer.

For instance, I have trouble with the terms 'double' and 'twin' and their complications when applied adjectivally to a room or a bed or an occupancy. OTOH, the term 'lit matrimonial' is perfectly clear.

If you were talking about hostels or maybe super-cheap rooms for rent or couch surfing then it could mean bring your own bedding, all you get is a mattress.

But not in normal hotels - anything that is a regular hotel will provide bedding. I’ve not seen the no bedsheets wording, but I have seen “no top sheet”, so I am confident that it means that. You will have a bed with sheet, pillows, pillowcases, duvet and cover, and blanket if it’s in the cold season. No top sheet. That’s common in Europe, but maybe this hotel ran into trouble with American guests complaining.

As an aside, I don’t get the obsession with top sheets. I’m American and hate them. Don’t use them at home and find it so much easier. But this is one of those personal preference things that you just have to adjust to when traveling. Or bring a top sheet if you care that much.

As has stated previously, the hotel uses a duvet and duvet cover rather than a top sheet and blanket. The latter is not available.

I actually love the duvet and duvet cover and used it at home. I found I slept better and it was easier to maintain.

In regard to "twin" and "double"--a double room is one bed for two people. Usually full size but could be bigger. A twin is usually two single beds.

Thank you all for your valuable information. That's what I thought. The problem is that they shouldn't say "Bed sheets not available". What they mean is TOP sheet not available". Sheets involve both the contour and the top sheet. If they don't want to provide a top sheet because they offer a duvet, that's fine with me. Half of the hotels in Europe have this warning. Hotel.com should rectify this statement, as it is confusing. Just a couple of samples, if you want to find out by yourselves. Hotel Nor Nuova, Lirico and Morgana in Rome. See you in Italy next year...I hope.

Thanks for clarifying that you're reading something on hotels.com and not from the actual hotels themselves -- none of the three examples you list say anything on the English versions of their websites about not having bedsheets
https://www.hotelmorgana.com/en/luxury-room/

Even if this will be your first visit to Rome, please consider not staying over on that side near Termini.
If you were going to San Diego, would you stay in the Gaslamp quarter? If San Francisco, would you stay near Fisherman's Wharf?
Of course not - so why would you do the equivalent in Rome?

"Buy a silk sheet that fits inside a coke can",

If you look at the thread, you’ll see I never said that.

There are some places where you do provide your own linens. Or the linens are so skanky that you want your own. In that situation I suggested a silk travel sheet which was “about the size of a soda can” when packed in its stuff sack. I provided a link to said item so people could see for themselves.

But most places in Europe have linens and a duvet. In other places of the world it’s more of a guess. It really is dependent on the accommodations you choose.

The convusion of language, i have never used the term top sheet, for me a sheet is simply a sheet but i also have a mattress cover. Actual not sure i even own a sheet.........have been a duvet family for 40 +years

Having travelled extensively in Europe over the last 40+ years staying in numerous hotels ,I have never been told or seen the message "bed Sheets not available".
I have never been in a hotel where there no sheets on the bed ,many places will have a bottom sheet and a duvet with a covering that will be changed as often as they would change sheets.