acid

1. N-MASS An acid is a chemical substance, usually a liquid, which contains hydrogen and can react with other substances to form salts. Some acids burn or dissolve other substances that they come into contact with. 酸

...citric acid. …檸檬酸。

2. ADJ An acid substance contains acid. 酸性的

These shrubs must have an acid, lime-free soil. 這些灌木必須要有酸性、無石灰的土壤。

3. acidityN-UNCOUNT 酸性[oft N 'of' n]

...the acidity of rainwater. …雨水的酸性。