acid Definition

a chemical substance that has a pH lower than 7 and can react with a base to form a salt, typically corrosive or sour-tasting.

Using acid: Examples

Take a moment to familiarize yourself with how "acid" can be used in various situations through the following examples!

  • Example

    Lemon juice is acidic due to the presence of citric acid.

  • Example

    Stomach acid helps in the digestion of food.

  • Example

    Battery acid is highly corrosive and can cause severe burns.

acid Synonyms and Antonyms

Synonyms for acid

Antonyms for acid

Phrases with acid

  • rainfall made sufficiently acidic by atmospheric pollution that it causes environmental harm, typically to forests and lakes


    The effects of acid rain on the environment are devastating.

  • a rigorous or crucial test of the effectiveness or value of something


    The acid test for any new technology is whether it can be easily adopted by the general public.

  • a sharp or critical way of speaking


    She has an acid tongue and often makes sarcastic comments.

Origins of acid

from Latin 'acidus', meaning 'sour'


Summary: acid in Brief

'Acid' [ˈæsɪd] refers to a chemical substance with a pH lower than 7 that can react with a base to form a salt. It is typically sour-tasting and corrosive. Examples include stomach acid, battery acid, and lemon juice. Phrases like 'acid rain' and 'acid test' use 'acid' to denote environmental harm and a rigorous test, respectively. 'Acid tongue' describes a sharp or critical way of speaking.

How do native speakers use this expression?