What do you call a job offer that isn't a real offer yet?

single-word-requests

All the current answers are using language that is perhaps correct as a definition, but not what would actually work in your situation.

The word you want to use in your phrases is "opportunity." A job opportunity is when there is the opportunity for a job. Nearly no company would describe this as a job offer until an actual job offer has been made.

It is also a very general term that can be used regardless of which stage you are in the process. This has the added benefit of not being presumptuous of your application state. You could for example turn down another interview request or a formal offer or an informal offer all with the same word.

An interview request is NOT an offer in nearly all cases.

Thank you, but I am not interested in this opportunity.
I am considering two other opportunities at the moment.

However, once they commit to making an offer it would be considered a "verbal offer." This is the state where the company has indicated they intend to give you a formal job offer, but not the actual paperwork yet. It might include as you describe the expected salary but doesn't include all the specific information.

In this case, I would still use the word opportunity in both the above contexts. The reason is that while well intentioned a verbal offer does not guarantee a formal offer. On The Workplace we get questions about this all the time. But it is still an opportunity.

A company is interested in a person as a potential employee, and contacts that person. The company's representative describes the role, advertises the benefits, interviews the person etc.

When the job is available to apply for, you would consider it a job posting / position. Once you have applied, but without having reciprocated interest, it'd become a job application. It can be considered to become an opportunity once you have communication back/forth from the company.

The term position is much broader

a post of employment; job

Collins

While it is routinely used to describe an existing employment (What is your position in the company?), it is regularly used to describe prospective jobs.

It would fit in the context of both your examples.

Well, I have a sort of "non-answer". And that is that in common usage for those 2 exact examples you don't typically refer to an "offer" (or whatever you want to call it), you refer to the opening/position itself. Especially since no actual offer has been made.

Thank you, but I am not interested in your position.

I am considering two other openings at the moment.

A head-hunter contacting you about a position does not in any way imply that you are any closer to an offer than if you had contacted them about it, so no "tentative/prospective offer" language is needed.

I once worked for a company that had such a division (what I refer to as "head-hunters", staffing experts that sought out potential employees for a job opening). They contacted enough people to hold full rounds of interviews, you had no more likeliness of getting the job just because it was one that they were contacting you about vs. one you applied for. In fact, they purposefully would find very lowly qualified people and send them in to the interviewers to up the likelihood of the company taking someone (and therefore them getting their commission for finding them) by making the regular people look more qualified by comparison. So those people definitely were not any closer to a real offer, they were basically sacrifices.

If some sort of unofficial/spoken offer has actually been made (the OP does not specify it has, but for the sake of thoroughness), then it would technically would be called exactly that: an unofficial offer, and it would be completely appropriate to just refer to it as an "offer".

Thank you, but I am not interested in your offer.

Provisional offer does not fit here at all, because that is an actual offer that has been made but with provisions/conditions. That does not seem to be the case.

Prospective offer and potential offer fits the description the OP gives (i.e. an offer is expected but not yet actually given), but not at all the examples given. You wouldn't tell them you're rejecting their prospective offer that hasn't even been given yet, you'd tell them you reject the position (like the beginning of my answer). Likewise you wouldn't tell one potential employer you have "prospective offers" elsewhere. Until an offer has actually been made you'd still just say that they are other "openings" or "positions" you're interested in.

That's what makes this question a little hard to answer: the description and the examples don't actually fully mesh. You tend to be answering for one or the other.

It's a provisional offer.

See this standard UK HR industry letter template (from pohwer.net)

"Once I have heard back from you confirming that you have received this letter and are accepting my provisional offer of employment, I will contact your referees"

From provisional: