Is there a more specific name for uncount nouns such as: ‘furniture’, ‘equipment’, ‘luggage’, etc.?

The uncountable nouns, listed in the OP's question, are names for groups or collections of things.

The noun cutlery (in the US flatware) is usually singular and includes different items; knife, fork, spoon, teaspoon, etc. All of the aforementioned belong to the category of cutlery, taken individually they are countable: I bought two new knives and a fork (Yes), but we do not say I bought three new cutleries (No) even if the items ‘knife‘ and ‘fork‘ belong to a group called “cutlery”.

There doesn't appear to be a specific name for this special type of collective noun, a noun that is normally singular but encapsulates items that are normally countable. For example, although team is a collective noun, it is also countable, we can say “a team” and “several teams”. The same is not true for the noun money, the following sentences are considered ungrammatical (i) *“she has a money” and (ii) *“she has several monies”. Although Wikipedia's article on mass nouns distinguishes two different mass nouns, amorphous/nonsolid substances vs. objects, they fail to mention if either one has a specific name in linguistics.

In English (and in many other languages), there is a tendency for nouns referring to liquids (water, juice), powders (sugar, sand), or substances (metal, wood) to be used in mass syntax, and for nouns referring to objects or people to be count nouns. This is not a hard-and-fast rule, however; mass nouns such as furniture and cutlery, which represent more easily quantified objects, show that the mass/count distinction should be thought of as a property of the terms themselves, rather than as a property of their referents. For example, the same set of chairs can be referred to as "seven chairs" and as "furniture"; although both chair and furniture are referring to the same thing, the former is a count noun and the latter a mass noun

Thus the OP will have to create their own terminology, if professor Pallum can…

I'd call them “uncountable nouns that consist of countable units” which is long-winded but comprehensible. Otherwise,

uncount nouns with discrete subsets, or, collective mass nouns

For more information on the fascinating land of uncountable nouns see the following pdf files.

  1. Mass counts in World Englishes: A corpus linguistic study of noun countability in non-native varieties of English (link)

  2. Mass Terms by Francis Jeffry Pelletier, University of Alberta

  3. MASS EXPRESSIONS (95 pages) by Francis Jeffry Pelletier and Lenhartk. Schubert

UPDATE

Plural mass nouns and the compositionality of number
Paolo Acquaviva, University College Dublin

[…] mass terms also include nouns like footwear or furniture, which undoubtedly have minimal parts (a splinter or a table leg are not furniture). Reference to collections of discrete elements links plurals like books to this latter class of mass terms, [e.g. furniture] which have been called collective masses (Link 1998, 214, Bunt 1985, 304); this is where the similarities of count plurals and mass terms end.

elsewhere…

Uncountable collective nouns, such as "furniture" and "traffic", always denote diverse multiforms. The diversity results from abstraction of the basic level. What makes these words different from the type set nouns such as “threat” is that they also imply multiplicity of these diverse things

Source, p.204, 1995. Author: Piek Th.J.M. Vossen (Wikipedia)