酸性(さんせい)

酸性(さんせい) describes the acidic property of a substance — having a pH below 7. Used in chemistry, agriculture, environmental science, and everyday contexts like food and skincare.

COMMON COMPOUNDS:

• 酸性雨(さんせいう): acid rain
• 酸性(さんせい)土壌(どじょう): acidic soil
• 酸性(さんせい)食品(しょくひん): acidic foods
• 弱酸性(じゃくさんせい): mildly acidic (common in skincare products)

pH SCALE VOCABULARY:

• 酸性(さんせい): acidic (pH < 7)
• 中性(ちゅうせい): neutral (pH 7)
• アルカリ性(せい): alkaline/basic (pH > 7)

USAGE:
As a の-adjective: 酸性(さんせい)の溶液(ようえき) (acidic solution). Also used directly before nouns in compounds: 酸性雨(さんせいう). The term 弱酸性(じゃくさんせい) (mildly acidic) is widely known from skincare advertising.

HOMOPHONE:
Not to be confused with 賛成(さんせい) (approval, agreement).