Meaning – Definition and Validity of ‘Boop/Boope’

'Wherein' is generally only used in formal writing. The Oxford English Dictionary gives the following senses and quotes. I have given the most recent quote, from which you can tell that the word is no longer generally used.

1. In what (thing, matter, respect, etc.)?

   1891 - Oh, Britannicus! wherein have we offended?

2. In which (place, material thing, writing, etc.)?

   1888 - Peering keenly into the shadow wherein she stood

3. In, at, during, or in the course of which (time).

   1819 - Length of days Wherein to act the deeds which are the stewards Of their revenue.

4. In which (matter, fact, action, condition, etc.); in respect of which.

   1889 - There began a round of pleasure for Julia wherein she was the central figure.

5. Into which.

   1585 - We came to an anker very nigh the castle, wherin when our patrone would followe vs [etc.].

The specialised creation of a non- word is appropriate. It can be useful to think in terms of Venn Diagrams, where there might or not be overlap between the items in question, but there is often a global circle that provides the outer boundary of all items.

So the project might be (say) the marketing of hybrid vehicles, and the marketing of petrol-only vehicles can usefully be called "non-hybrid", since they are unrelated only with respect to their not being hybrids.

Australia had a prime minister who famously described his election platform as containing core and non-core promises, and I expect everyone knew what he meant.