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From Japanese 形容動詞(けいようどうし) (keiyōdōshi), itself a compound of 形容(けいよう) (keiyō, “description; form”) + 動詞(どうし) (dōshi, “verb”).
Etymology from Wiktionary, CC BY-SA 4.0.
Today it means: An adjectival noun. Full definition →
From Japanese 形容動詞(けいようどうし) (keiyōdōshi), itself a compound of 形容(けいよう) (keiyō, “description; form”) + 動詞(どうし) (dōshi, “verb”).
Etymology from Wiktionary, CC BY-SA 4.0.