Apposition

Apposition is a grammatical construction in which two elements, normally noun phrases, are placed side by side, with one element serving to identify the other in a different way; the two elements are said to be in apposition. One of the elements is called the appositive, although its identification requires consideration of how the elements are used in a sentence.

For example, in the two sentences below, the phrases Alice Smith and my sister are in apposition, with the appositive identified with italics:

Traditionally, appositions were called by their Latin name appositio, although the English form is now more commonly used. It is derived from Latin: ad ("near") and positio ("placement").

Apposition is a figure of speech of the scheme type, and often results when the verbs (particularly verbs of being) in supporting clauses are eliminated to produce shorter descriptive phrases. This makes them often function as hyperbatons, or figures of disorder, because they can disrupt the flow of a sentence. For example, in the phrase: "My wife, a nurse by training, ...", it is necessary to pause before the parenthetical modification "a nurse by training".

A restrictive appositive provides information essential to identifying the phrase in apposition. It limits or clarifies that phrase in some crucial way, and the meaning of the sentence would change if the appositive were removed. In English, restrictive appositives are not set off by commas. The sentences below use restrictive appositives. Here and elsewhere in this section, the relevant phrases are marked as the appositive phrase_A or the phrase in apposition_P.

A non-restrictive appositive provides information not critical to identifying the phrase in apposition. It provides non-essential information, and the essential meaning of the sentence would not change if the appositive were removed. In English, non-restrictive appositives are typically set off by commas. The sentences below use non-restrictive appositives.

The same phrase can be a restrictive appositive in one context and a non-restrictive appositive in another:

If there is any doubt that the appositive is non-restrictive, it is safer to use the restrictive form. In the example above, the restrictive first sentence is still correct even if there is only one brother.

A relative clause is not always an appositive.

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