How to Say "Adjective" in Japanese

形容詞

keiyōshi[ke̞ːjo̞ːɕi]

The English word "adjective" is translated into Japanese as 形容詞 (keiyōshi).

In a grammatical context, 形容詞 refers to a word that modifies a noun or describes a noun's referent.

Meaning: (grammar) a word that modifies a noun or describes a noun’s referent (noun)

What does it mean word for word?

The word 形容詞 is composed of three parts: 形 (shape/form), 用 (use/purpose) and 詞 (word/part of speech).

keiyōshi

Because 'i-adjectives' can be conjugated for tense, the word 'beautiful' can change its ending to mean 'was beautiful' without needing a separate verb.
The term 形容詞 was first cited in 1870, during the Meiji era. This was a period when Japan was rapidly importing Western grammatical concepts to translate and categorize its own language.
In Japanese grammar, 'na-adjectives' are actually classified as 'adjectival nouns' because they behave more like nouns than English adjectives do.

イタリア語では、英語と異なり、形容詞の配置を変えることができる。
In Italian, unlike English, adjective placement can vary.
This sentence is useful for discussing how the placement of 形容詞 can vary in Italian compared to English.
Tatoeba #1615581 by Meow, translation #11232955 by pip
名詞を修飾するもの（形容詞、または形容詞相当語句）。
Things that modify nouns (adjective, or adjectival equivalent).
This sentence is useful for defining things that modify a noun as an 形容詞 or an adjectival equivalent.
Tatoeba #75098 by fcbond, translation #328621 by fcbond
所有形容詞
a possessive adjective
This sentence is useful for the term regarding a possessive 形容詞.
Wiktionary
4 more sentences on Tatoeba

Two students are discussing a Japanese grammar textbook.

陽葵 Himari

これは形容詞の使い方の練習問題ですか？
Kore wa keiyoushi no tsukaikata no renshuu mondai desu ka?
Is this an exercise for how to use adjectives?
大翔 Hiroto

はい、形容詞を学ぶための問題です。
Hai, keiyoushi o manabu tame no mondai desu.
Yes, it is a problem for learning adjectives.
陽葵 Himari

大翔さんは、形容詞のルールを理解していますか？
Hiroto-san wa, keiyoushi no ruuru o rikai shite imasu ka?
Hiroto, do you understand the rules for adjectives?
大翔 Hiroto

陽葵さん、少し難しいですが、頑張ります。
Himari-san, sukoshi muzukashii desu ga, ganbarimasu.
Himari, they are a bit difficult, but I will do my best.

Sources

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