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悪性 (あくせい) Japanese meaning | Kotomora
Common word Freq. Frequency Top 20,000 Meanings 1
noun which may take the genitive case particle 'no', noun
malignant ; virulent ; pernicious
Primarily a medical term describing diseases, especially cancers, that are aggressive or life-threatening. Also used in fixed phrases like 悪性貧血 (pernicious anemia).
が
流りゅう
行こう
し
て
いる
。
A virulent strain of influenza is going around.
Similar words 良りょう 性せい 良性 means 'benign' and is the direct antonym of 悪性 in medical contexts.
悪あく 質しつ 悪質 means 'malicious' or 'of poor quality', referring to intent or nature, while 悪性 is strictly medical or biological.
Etymology Compound of 悪 (aku, 'bad, evil') and 性 (sei, 'nature, property'). The medical sense is a direct adaptation of the Western medical concept of malignancy.
