An editor asked me which of these constructions is correct: a friend of John’s or a friend of John. It is idiomatic in standard English to say or write a friend of John’s. I explained that we use a possessive pronoun in this construction: He is a friend of mine. I am a friend of his. Therefore, when we use a person’s name in this “of” construction, we make it possessive.
This construction is often called a double possessive, but it also is called a double genitive. “The Writer’s Digest Grammar Desk Reference” and “The Gregg Reference Manual” point out that the use of the double genitive can avert misunderstanding. A painting of Jennifer shows Jennifer, but a painting of Jennifer’s belongs to Jennifer.
“Working With Words” cautions that the double possessive is used only to refer to people, not inanimate objects: Joan is a friend of Tina’s, but not Joan is a fan of the show’s. That should be Joan is a fan of the show.
World Wide Words and The Mavens’ Word of the Day have explanations of the double possessive that go into more detail.
This article was originally posted by the Raleigh News & Observer, a subsidiary of The McClatchy Co.; is posted here to provide continuity; and is copyright © 2011 The News & Observer Publishing Company, which reserves the right to remove this post.