What is "adjectival noun"

n. 1 (context linguistics English) A noun that functions as an adjective 2 In Japanese grammar, a specific parts of speech, categorized in Japanese as 形容動詞 (keiyō dōshi). Some of these words can be used as regular nouns, and all can be used as adjectives when followed by the postfix な (na), in contrast to Japanese common adjectives, 形容詞 (keiyōshi).

In descriptions of the Japanese language, an adjectival noun, adjectival, or na-adjective is a noun that can function as an adjective by taking the particle 〜な -na. (In comparison, regular nouns can function adjectivally by taking the particle 〜の -no, which is analyzed as the genitive case.) Adjectival nouns constitute one of several Japanese word classes that can be considered equivalent to adjectives.

In their attributive function, Japanese adjectival nouns function similarly to English noun adjuncts, as in "chicken soup" or "winter coat" – in these cases, the nouns "chicken" and "winter" modify the nouns "soup" and "coat", respectively. Japanese adjectival nouns can also be used predicatively – in that use, they do not take the -na suffix, but normally combine with forms of the copular verb.

Adjectival noun may refer to:

• Adjectival noun (Japanese), also called adjectival or na-adjective
• Noun adjunct, a noun that qualifies another noun, like college in college student
• Nominalized adjective, an adjective which has come to function as a noun, as in the rich and the poor