My first thought was that they are collective nouns. However, to be precise, I'm talking about nouns that refer to a group of similar - but not the same - things.
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A group of similar but not same things is generically a set of things.
For aircraft, includes the different kinds of planes, dirigibles, drones, and so on. For cutlery there are forks, knives, spoons, fish slices, salvers, sporks, and so on.
Another example of a word like this is 'animal'. There are carnivores, bovines, rodents... and among carnivores there are felines, ursids, canines... among canines dogs, wolves foxes...and it keeps going.
The word to describe the word for the larger set in relation to word for the subsets is
For example, 'aircraft' is a hypernym of 'dirigible' (and the other direction is 'dirigible' is a hyponym of 'aircraft').
The words 'aircraft' and 'cutlery' are obviously generic terms describing a range of more particular things, but from the examples I gave you can see that you can go up in generality and down in specificity for most any word. 'Aircraft' is itself a hypernym, but is also is a hyponym of 'transport' which is itself a hyponym of 'machine' and so on.