Say there is a glass of water, and someone drank it (dipping their lips, i.e. not from a distance pouring water into their mouth). Now the glass of water is (somewhat) impure, containing the saliva of the person.
What is the word in English that denotes the water is impure in the sense that the water has been drunk by someone?
I'm not sure how widely used this term is, but on road trips as a child in New Zealand I remember our father admonishing us for poor technique in drinking straight out of a shared soda bottle, causing backwash of spit into the bottle. Wiktionary has it as the 4th definition:
The saliva, spit or food particles that have flowed back into a drink after someone has drunk from it.
I wouldn't use it in a very formal situation however. It's a step further from explicitly talking about saliva but still close enough to be a bit crass.
This would depend on how severe you consider the outcome to be - contaminated is the most obvious, but strongly suggests that the water is now undrinkable, while dirty is more of a middle ground.
I can't think of a single word that has the meaning of "containing saliva", so I would probably say has been drunk from or similar.
If the glass was empty, then you would often hear it described as used but that doesn't really work well if the glass is still fairly full.
used has indeed been drunk from. There are probably a thousand and one other ways to use a glass, but all of them combined will be a fraction of a percent of overall usage.
I upvoted Mike Brockington's answer, but I wanted to specifically put forward "that glass is used" and "that glass has been drunk out of" as natural ways to express what you want in ordinary conversation. It's what you would say if someone picked up a glass from the counter that you knew someone else had already drunk from. You probably wouldn't say it was "contaminated", partially (I think) because that tends to reflect poorly on the person who had drunk from the glass. (I'm in the US, so this may be specific to US English.)
Added later: I also don't think you would ordinarily say "that glass has backwash" in that context. I remember, from my childhood, another kid telling me "the last sip from a bottle of Coke is 90% backwash". So it's certainly the word for the saliva that gets left behind, but if all you want to indicate is that somebody has put the glass to their lips, saying it "has backwash" is probably a bit strong.
There is not a specific word or phrase that maps to what you want, but typically when someone drinks from a glass [or uses pretty much any dishware or shared object for that matter] there is now an implied ownership relationship, eg: "Whose glass is this?" and "Don't drink from that glass, it's Juztcode's.", even if they do not literally own the glass.
Now that I think of it there is probably a cultural component in that implication of the glass that someone's using as being "dirty" or "contaminated", as suggested by others, could be interpreted a reflection on the user as the same, or that the thing was unclean to being with.
However, once the person is finished using it that implication of ownership falls away and saying something like "Let me clear away these dirty dishes." or "Please put your dirty dishes in the sink." wouldn't necessarily cause any offense.
That said, the state of the water itself would be a secondary implication deriving from the state of the glass, or might be referred to instead of the glass, eg: "That's Jusztcode's water.".
The most common terms are very simple: this would be a “used” or “dirty” glass.
I'm not aware of any one word in English that means "someone has already drunk from this glass". If there is such a word, it's not in common use. At least, not among people I talk to.
You have to use several words or a full sentence to describe what you are trying to say. Like, "Someone has been drinking from this glass, it may not be sanitary."
It sounds like you're looking for an English translation of the South Asian concept of Jootha, known by a variety of spellings and pronunciations in languages in the region, but generally describing food or drink that has been 'touched' by another person.
Among English speaking adults, the concept tends more towards ownership rather than contamination. If John has had a drink from a glass we simply say that it is "John's water", or "John's glass". This is primarily to avoid suggesting that John had 'contaminated' the glass, or was unclean in some way as this could be seen as being rude. Possession is therefore used as a polite way to avoid conjuring ideas of germs or uncleanliness which most people don't want to be associated with. Of course, we don't want to eat food someone has already eaten from either, but it tends simply to not be talked about so directly.
If you're at a social gathering and there is food out on tables you might ask if a particular item "is for everyone" or whether it is someone else's. To say that a plate is "John's plate" will be understood to mean that he has selected items out on offer for everyone and has placed them on a plate for himeself (which he may have already eaten from, or is intending to).
Food that is out on offer "for everyone" is generally handled with utensils or tools so as to not 'contaminate' the food, and it is generally understood that if food is "for anyone" then you can assume it hasn't been tasted or touched by anyone else. For any food that has, we tend to simply say that the food now 'belongs' to someone, and the usual social rules for taking, using, or touching someone's property then also apply by extension to the food.
How about, “That’s not yours.” Or, “That’s no longer clean.” That seems to work in the U.S. Especially now, during the pandemic.
Although there are phrases to indicate that water is no longer drinkable (non-potable, contaminated, etc.), there is really not a universal phrase to indicate that drinkable water should not be drunken by someone else. At least, not in polite company. Generally, we will do things like mark our individual receptacles with writing, symbols, charms, or drink containers of differing colors to indicate that one should drink only from their own beverage. Generally, it is just understood not to drink from/of any item that you can not positively identify as untampered, and yours and yours alone. Especially around strangers.
However, there is a universal phrase in the U.S.A. for a liquid that is to be shared out of the same container. It is the same phrase for sharing a meal item from a central dish for your table (as opposed to a buffet table). It is called ”Family-Style”. It is very typical for alcoholic beverages (or, sometimes even water) in outdoor or rustic environments like camping, farming, sports, and field work to be shared Family-Style. Although, it is typically considered impolite, uncouth, and socially unacceptable to place your mouth or any other body part on the opening of a communal beverage container when there are individual containers to which you can transfer the beverage, even amongst your own family. It is not uncommon to share or allow a family member or really really close friend to taste an item from your own container or utensil.
If you're trying to tell someone else not to drink from the glass you could just say "<person> already drank from that". Which would be acceptable in any situation. As noted English has no single word for this concept.
In a non-formal situation I'd say "it has <person>'s cooties".
In my mind proper drinking technique does not leave "backwash" so claiming that would be an insult to the drinker.
Contains spittle from (personal nomenclature here).
As others have said, there is no word for this concept in English. Kids would say "It's got germs in it".
Possible words you could use are defiled, tainted, spoiled or contaminated, but these all suggest that something toxic, such as a poison, has been added to the water.
Defiled is often used when "pure" things, such as nature, get spoiled.
Cambridge Dictionary definitions
Defile: to spoil something or someone so that that thing or person is less beautiful or pure
Taint: to spoil something or give it an unpleasant quality
Spoil: to destroy or reduce the pleasure, interest, or beauty of something. When food spoils or is spoiled, it is no longer good enough to eat.
Contaminate: to make something less pure or make it poisonous
In the UK, crudely and using slang, you might say:
You've gobbed in it.
or
It's been gobbed in.
You can find broad definitions for "gob" and "gobbed" in dictionaries, but this particular meaning seems only to be listed in tongue-in-cheek street ones like the Urban Dictionary.
It seems words get into the dictionary as per their usage stats (According to Marriam-Webstar). So, let's call it spottled water. Any comments?
