Are we there yet?
I know that this sentence usually means
Have we got there so far (‘at this time’)?
and it is even somewhat idiomatic.
But ‘yet’ has another meaning, ‘still’, which may give the sentence the opposite meaning:
Are we still there (‘even so far’)?
Is it totally impossible for the ‘yet’ to mean ‘still’ in this sentence? If so, why is it?
Asking if we are still somewhere would imply that we've already been there for a relatively long time. So, I can imagine boarding an airplane and dozing off shortly after I get into my seat. I might wake up and find that the aircraft is still on the tarmac, perhaps due to a weather delay or mechanical problem. In a situation like that, I might say bemoaningly:
Oh, are we still here?
I suppose I could substitute yet for still in that sentence, and change the word order:
Oh, are we here yet?
I think that's grammatical; however, as others have said, it would sound like I'm auditioning for a Shakespearian play.
If we really wanted to use there instead of here, we could imagine it's my uncle Ebenezer who is stuck on the plane, and he just texted me to let me know he is still in Chicago, even though he was supposed to be taking off almost an hour ago. In that case, when I share the news with my family (who are all anxious to see Uncle Ebenezer), one of them might cry out in dismay:
Oh, is he there yet?
meaning:
Oh, is he still there?
but again, it would sound dreadfully old-fashioned and melodramatic, and therefore I can only imagine it said that way for humorous effect.
Now, as for your wording: because "we" is in the first person, and "there" often refers to some place away from the speaker, I'm having a hard time construing a scenario where the actual sentence would be combine "we" with "there" as you did:
Are we there yet?
unless there refers to a figurative place rather than a literal one. Perhaps you and your spouse are still arguing about a long-time bone of contention, and you, tired of the argument, say:
Are we having this fight yet again?
Would could become shortened to:
Are we there still?
And then:
Are we there yet?
But if that's the way you said it from the outset, I'm not sure how well-understood you'd be. You might even start another long argument.
There is implied meaning and interpreted meaning. Implied meaning is the most direct and simple interpretation of a phrase, and although it could vary from person to person, "Are we there yet?" can have only one obvious implied meaning here, which is "Have we finally arrived?"
A phrase can have many interpreted meanings, and while the most obvious is "Have we arrived yet?", another interpretation (albeit very very obscure) is "And still are we there?" I stress though that it is very obscure simply because the implied meaning covers this interpretation almost entirely.
That said, if communication has any importance here, the implied meaning is all you should take into consideration.
Yet and still: basic clarification
Is he here yet? The question implies he is not at a place as of a particular time.
Is he still here? The question implies he continues to be at a place at a particular time.
Therefore, they mean completely different things.
"Are we there yet" is idiomatic. It suggests that the speaker is assuming the answer is negative (and would be surprised to hear the contrary). If the assumption is that we arrived, the appropriate word would be already: "are we there already?"
As Cambridge dictionary notes:
Already refers to things which have happened or which people think may have happened. Yet refers to things which have not happened or which people think may not have happened.
In declarative sentences the distinction is clear:
We are not there yet.
We are already here (for some time).
And if we are expected to leave at some time:
As a side note, there refers to a place that is not here, and here is by definition where the speaker is located. So "are we there yet" logically invites the answer "no", and any other answer would be surprising; this is part of the idiomatic sense this sentence has.
Your question suggests that
‘yet’ has another meaning, ‘still’
This is not exactly correct. In some occasions yet and still may seem interchangeable, but there is still a difference:
(Statement A), yet (statement B).
(Statement A). Still, (statement B).
In both cases, statement B is implied to be true, and be somewhat contradictory to statement A. Using yet emphasises the contradiction, and suggests that statement A is false. Using still diminishes the contradiction and suggests that statement A may also be true.
Specific examples:
Many people think cellular phones are hazardous, yet there is insufficient evidence of any health problems associate with cellular phone usage.
There is insufficient evidence of any health problems associate with cellular phone usage. Still, many people think cellular phones are hazardous.
(See "Yet as a conjunction" here and "still in front position" here.
