In “an idea of Hölderlin’s”, is “of” a partitive or a genitive?

Question

We often use these constructions. A friend of mine is probably the most common.

I have often wondered, being an English teacher, whether the function of the preposition of in such contexts is that of a partitive (it implies an idea of splitting something into parts, so a friend of mine is a part of the whole of my friends) or a genitive (it implies the idea that something belongs to something else, so an idea of Hölderlin’s would mean Hölderlin’s idea).

I realize the distinction is subtle. Is there a professional scholar in linguistics here who can clarify?

Answer 1

From your question, I am not sure if you want an answer only for the phrase “a friend of mine”, or if you are looking for possessive phrases in general. So here are the definitions for partitive and the various genitives that may apply to your situation.

I hope this clears up any confusion.

---

A partitive does imply ”a distinct quantity that is part of a larger whole”, but the usual determiners for partitives are shown by: some of; any of.

Jenny ate some of the strawberries.

A genitive is the possessive case (in English), and is marked either with the suffix ’s or with an of phrase after a noun.

Jenny is a friend of mine.

A double genitive is indicated by a noun, the preposition of followed by a possessive noun.

Jenny likes Tommy, who’s a friend of Karen’s.

A group genitive is the possessive cases with a misdirection in the possession because the suffix 's appears at the end of a noun phrase where the final word in that noun phrase is not the head (or only head) of the larger phrase.

Jenny is allergic to the man next door’s dog.

An independent genitive is a construct where the noun following the possessive is omitted.

Jenny went to the doctor’s after she fell down the stairs.