Noun adjunct

In grammar, a noun adjunct or attributive noun or noun (pre)modifier is an optional noun that modifies another noun; it is a noun functioning as a pre-modifier in a noun phrase. For example, in the phrase "chicken soup" the noun adjunct "chicken" modifies the noun "soup". It is irrelevant whether the resulting compound noun is spelled in one or two parts. "Field" is a noun adjunct in both "field player" and "fieldhouse".

Adjectival noun is a term that was formerly synonymous with noun adjunct but is now usually used to mean "an adjective used as a noun" (i.e. the opposite process, as in the Irish meaning "Irish people" or the poor meaning "poor people"). Japanese adjectival nouns are a different concept.

Noun adjuncts were traditionally mostly singular (e.g. "trouser press") except when there were lexical restrictions (e.g. "arms race"), but there is a recent trend towards more use of plural ones. Many of these can also be and/or were originally interpreted and spelled as plural possessives (e.g. "chemicals' agency", "writers' conference", "Rangers' hockey game"), but they are now often written without the apostrophe, although decisions on when to do so require editorial judgment. There are morphologic restrictions on the classes of adjunct that can be plural and nonpossessive; irregular plurals are as nonpossessive adjuncts (for example, "men clothing" or "women magazine" are solecistic to fluent speakers).

Fowler's Modern English Usage states in the section "Possessive Puzzles":

Five years' imprisonment, Three weeks' holiday, etc. Years and weeks may be treated as possessives and given an apostrophe or as adjectival nouns without one. The former is perhaps better, as to conform to what is inevitable in the singular – a year's imprisonment, a fortnight's holiday.

Noun adjuncts can also be strung together in a longer sequence preceding the final noun, with each added noun modifying the noun which follows it, in effect creating a multiple-word noun adjunct which modifies the following noun (e.g. "chicken soup bowl", in which "chicken" modifies "soup" and "chicken soup" modifies "bowl"). There is no theoretical limit to the number of noun adjuncts which can be added before a noun, and very long constructions are occasionally seen, for example "Dawlish pub car park cliff plunge man rescued", in which "Dawlish", "pub", "car park", "cliff", and "plunge" are all noun adjuncts. They could each be removed successively (starting at the beginning of the sentence) without changing the grammar of the sentence. This type of construction is not uncommon in headlinese, the condensed grammar used in newspaper headlines.

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