ETYM Latin appositio, from apponere: cf. French apposition. Related to Apposite.
Juxtaposition; Grammar, putting two nouns or phrases together as attributive or adjunct terms; relationship of such nouns or phrases.
In grammar, the placing of a noun or noun phrase next to another that refers to the same thing (“We’ll take the easiest route, the east ridge, to the top”). The word or phrase in apposition is marked off from its antecedent (to which it refers) by a pair of commas.
A grammatical relation between a word and a noun phrase that follows.