apposition

Apposition is when two nouns or phrases are placed back to back and both nouns refer to the same thing.  For example, in the following sentence,

We visited the home of Harriet Beecher Stowe, the author of Uncle Tom’s Cabin.

“Harriet Beecher Stowe” refers to the same person as “the author of Uncle Tom’s Cabin”. Hence, we would say that “the author of Uncle Tom’s Cabin” is in apposition to Harriet Beecher Stowe.

Jim, a student at Harvard, failed his entrance exam.'student' is in apposition to 'Jim'.

The professor of philosophy, Mr. Owen, was in a car accident and broke his femur, the largest bone in the human body.'Mr. Owen' is in apposition to 'professor'. 'bone' is in apposition to 'pelvis'.

A genitive of apposition is when the genitive noun is in apposition to the head noun as in “the earnest of the Spirit” (2 Corinthians 5:5) which is to say the earnest which is the Spirit.  GGBB p95

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