What is this kind of "___ of ___" syntax called?

Solution 1:

The noun of noun construction is called a partitive when used to refer to parts of wholes. For example: a slice of bread, a majority of the people. I am not aware of a term that covers all such specific noun of noun constructions, including the examples you give.

A general term, however, is collocation. So the preposition of collocates with the nouns idea, use and point, as in your examples. Other noun + of collocations include: cause of, love of, fear of, risk of.

Other nouns collocate with different prepositions: cure for, case for, rise in, belief in, information on, report on, etc.

There are more noun+preposition collocations on the excellent 7ESL site.