Here's the definition of collective noun in Quirk*
"¢ These differ from other nouns in taking as pronoun coreferents either singular it and relative which or plural they and relative who without change of number in the noun (the army: in which / they / who/.... Consequently, the verb may be in the plural after a singular noun, though far less commonly in AmE than BrE.
The committee has met and it has / have met and they have rejected the proposal.
The difference reflects a difference in point of view; the singular stresses the nonpersonal collectivity of the group, and the plural stresses the personal individuality within the group.... _______
Then Quirk gives a list of examples of collective nouns, which includes, of course, family, government, committee, company, department, flock, population, crew, group and staff, to name a few. Of the nouns listed, group and majority might include inanimate objects.
We have already decided that bunch does, although "bunch" is not on the list. "Bunch" does conform to the definition above; we can say, "There's / There are a bunch of people in the hall," and "There's / There are a bunch of bananas on the table."
Quirk also lists these nouns as collective noun, appearing in the singular only with the definite article:
the aristocracy the bourgeoisie the church the clergy the elite the gentry the intelligentsia the laity the press the public the rank and file the youth (of today)
There are also some examples of collective nouns as proper names:
the commons (UK) the Congress (US) Parliament the Unived Nations the Vatican\the United States _______
Now, in Wikipedia – which often has some accurate information – there is this definition of "collective noun":
"¢ In linguistics, a collective noun is a word used to define a group of objects, where "objects" can be people, animals, inanimate things, concepts, or other things. For example, in the phrase "a pride of lions", pride is a collective noun.
Most collective nouns encountered in everyday speech (such as "group") are mundane and are not specific to one kind of constituent object (for example, the uses "group of people", "group of dogs", and "group of ideas" are all correct uses).
Others, especially words belonging to the large subset of collective nouns known as terms of venery (words for groups of animals), are specific to one kind of constituent object (for example, "pride" as a term of venery refers to lions"” but not to dogs or llamas). (Terms of venery are further discussed in a subsequent section.)
Wikipedia includes terms of venery (words for groups of animals) in a subset of collective nouns.
Not all of these can be termed collective nouns, though. For example, "a hand of bananas" would always be singular. So would, I believe, "punnet, clutch," and "string," but I am not absolutely positive.
For a previous treatment of collective nouns, please see the Grammar Exchange Archives: collective nouns
Rachel _______ *A Comprehensive Grammar of the English Language by Quirk et al. Longman 1985