apposition

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. Grammar A construction in which a noun or noun phrase is placed with another as an explanatory equivalent, both having the same syntactic relation to the other elements in the sentence; for example, Copley and the painter in The painter Copley was born in Boston.
2. n. Grammar The relationship between such nouns or noun phrases.
3. n. A placing side by side or next to each other.
4. n. Biology The growth of successive layers of a cell wall.

Century Dictionary and Cyclopedia

1. n. The act of adding to or together; a setting to; application; a placing together; juxtaposition.
2. n. In grammar: The relation to a noun (or pronoun) of another noun, or in some cases of an adjective or a clause, that is added to it by way of explanation or characterization. Thus, “Cicero, the famous orator, lived in the first century before Christ”; “On him, their second Providence, they hung.” In languages that distinguish cases, the noun in apposition is in the same case as the word to which it is apposed. The same term is also used of an adjective that stands to the noun (or pronoun) to which it refers in a less close relation than the proper attributive, being added rather parenthetically, or by way of substitute for a qualifying clause. Thus, “They sang Darius, great and good”; “Truth, crushed to earth, shall rise again.” Rarely, it is applied to a clause, whether substantive or adjective, that qualifies a noun (or pronoun) in an equivalent manner. Compare attributive and predicative.
3. n. The relation of two or more nouns (or a noun and pronoun) in the same construction, under the above conditions. Knights Templars, lords justices, Paul the apostle, my son John's book (where son is also possessive, the sign of the possessive case being required only with the final term), are examples of nouns in apposition; “I Jesus have sent mine angel” (Rev. xxii. 16) is an example of a pronoun and noun in apposition.
4. n. . In rhetoric, the addition of a parallel word or phrase by way of explanation or illustration of another.
5. A public disputation or examination: now used only as a name of Speech Hay in St. Paul's School, London.

Wiktionary

1. n. grammar A construction in which one noun or noun phrase is placed with another as an explanatory equivalent, either having the same syntactic function in the sentence.
2. n. The relationship between such nouns or noun phrases.
3. n. The quality of being side-by-side, apposed instead of being opposed, not being front-to-front but next to each other.
4. n. A placing of two things side by side, or the fitting together of two things.
5. n. In biology, the growth of successive layers of a cell wall.
6. n. rhetoric Appositio

GNU Webster's 1913

1. n. The act of adding; application; accretion.
2. n. The putting of things in juxtaposition, or side by side; also, the condition of being so placed.
3. n. (Gram.) The state of two nouns or pronouns, put in the same case, without a connecting word between them; as, I admire Cicero, the orator. Here, the second noun explains or characterizes the first.

WordNet 3.0

1. n. a grammatical relation between a word and a noun phrase that follows
2. n. (biology) growth in the thickness of a cell wall by the deposit of successive layers of material
3. n. the act of positioning close together (or side by side)