Am 21.02.2020 um 18:42 schrieb SuStel:

The word is /genitive./ The first noun [...]

*bIQ bal* /water jug

[...]

Apposition, on the other hand, is where two nouns or noun phrases are
side by side, and one further identifies the other.

Okay, I think I understand. But how is the following interpreted then?

We were told the word {wab labwI'} means "radio". We were also told that
if it was need to distinguish the broadcaster from the device, you may
add {jan}.

Expanding this, I could probably say {wab labwI' qach}, {wab labwI'
malja'}, {wab labwI' loD}... etc.

The second part of this nn-construction might be labeled as "identifier".

In linguistics, the correct word for the second noun would be the head noun.

I may even accept that it's still a genetive construction, BUT why is it
turned around?

For instance, in {bIQ bal} the identifier comes first: WATER bottle
instead of "BEER bottle".

In the phrase {wab labwI' jan}, it's not {wab labwI'} identifiying the
kind of {jan}, it's the {jan} word which is telling you what kind of
{wab labwI'} you talk about.

You're confusing how Okrand is describing something and the grammar behind it. When Okrand says you can distinguish which kind of wab labwI' by adding a word like jan, what he means is you can talk about a different head noun to make the distinction. Instead of talking about a transmitter, which can be a person or a device the person is using (in English, too), you can talk about a device, which is only one thing. wab labwI' jan is a noun-noun construction in which the genitive noun (phrase) is wab labwI', and the head noun is jan. Okrand is not saying you're adding a genitive noun, and you're not; he's only giving you a way to clarify that you mean a device instead of a person.

In addition to thins thought, {wab labwI'}
CAN stand alone and still mean the same when context is clear.

More specifically, it can stand alone when the speaker doesn't need to know whether you're talking about a person sending a signal or the device used to send that signal.

If the
word {bIQ} stands alone, it is never connected to the idea of a bottle,
but {bal} is.

Because there is no double possibility as to what bIQ means.

Compare this:

{wab labwI' vIpoQ. wab labwI' jan vIpoQ.}
I need a radio. I mean, a radio DEVICE.

As opposed to the person who transmitted sounds, who is also a wab labwI'.

{bal vIpoQ. bIQ bal vIpoQ.}
"I need a bottle. I mean, a WATER bottle"

See the difference?

In the first sentence, you're changing head nouns to make it clear what you're talking about. In the second sentence, you're adding a genitive noun to clarify the sense of the head noun, but never changing the head noun.

Now this is my serious question:
Where is the difference? And does it have a name?

These are two completely different grammatical operations, so there is no name.

-- 
SuStel
http://trimboli.name