murder : crows :: _ : collective nouns
Sorry, no multiple choice this time.
The only published term I can find is a confusion of collective nouns, this is Jim Wegryn's coinage from A Barrel Full of Fun.
But personally I prefer misterben's contrivance.
Wikipedia's entry on terms of venery lists "nouns of assembly" as an idiom with the same meaning.
Later in wiktionary appendix entry you also find
These are all synonyms for 'terms of venery', maybe these are interesting due to the fact that terms of venery, strictly speaking refer to collective nouns of animals. I will use them interchangeably hence forth in the examples, please substitute all variants when evaluating certain proposals.
Now, you question says you are looking for a collective noun for terms of venery i.e. nouns of multitude in which you could say
A slight problem here is that terms of venery are most apply to single words; but overlooking this I would say that what is crucial here is that you are talking about assembly of words and therefore (maybe too obvious) a candidate to consider is:
For lexicon you can interchange corpus, and maybe dictionary, almanac, encyclopedia and so on.
On the chance that the above term is missing what you are thinking about completely, then let me question a part of your clarification:
The issue came up after we decided to name some software projects after collective nouns. Given this, we felt that the logical thing to name the document describing the overall architecture of these projects would be the collective noun that refers to a collection of collective nouns.
It seems to me that you might be mixing something here
I would say that a good test for what is applicable is to use a construct:
where things are your projects (or something more specific) and see if that really points to the thing you want to talk about (for example "a document" is almost certainly not "a group of" anything; although it might contain a group or a collection of terms; which again is a lexicon).
If a construct "a group of ..." works semantically only then you should search for adequate collective noun. In another words - then this can be seen as purely aesthetic substitution, an aesthetic improvement.
So, a lexicon works if we look at collective nouns as words, but in terms of systems it might be completely wrong. Lexicon refers only to the aspect of linguistic of these terms, ignoring the fact that these are some systems, when normally for example between bees and swarm (collective noun and the noun) there exists a deeper connection - two bees don't make a swarm, but when there are enough you have a multitude, an assemblage that is significantly different from a single or a few specimens (different intelligence, different ways to hunt, etc).
If you need such a word (from the context of systems) for your case then realize that it is not enough to specify that the names of the projects are collective nouns and that you will have to describe commonalities between these projects for us to be even able to think about adequate word.