An acid neutralizer is a chemical substance that is used to reduce the acidity of a solution. There are many different synonyms for the term acid neutralizer, including pH modifier, alkalizer, base, neutralizer and buffer. Each of these words essentially refers to a substance that is used to counteract the effects of an acid, including stomach acid, corrosive chemicals, and other acidic substances. While acid neutralizers can be found in a wide range of different forms, from tablets and powders to liquids and gels, each of them serves the same basic function of reducing the acid levels of a given solution, protecting against erosion and other negative effects.