Definition of 'acid'

Word Frequency

acid

(æsɪd )

Word forms: plural acids

1. variable noun

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.

...citric acid.

Acids in the stomach destroy the virus.

2. adjective

An acid substance contains acid.

These shrubs must have an acid, lime-free soil.

acidity (æsɪdɪti ) uncountable noun

...the acidity of rainwater. [+ of]

Synonyms: sharpness, bitterness, harshness, pungency More Synonyms of acid

Synonyms: sourness, bitterness, sharpness, pungency More Synonyms of acid

3. graded adjective

An acid fruit or drink has a sour or sharp taste.

A tomatillo is a small green Mexican fruit with a delicate and slightly acid taste.

acidity uncountable noun

Taste, and adjust the acidity of the fruit by adding a pinch of sugar if required.

Synonyms: sharpness, bitterness, harshness, pungency More Synonyms of acid

Synonyms: sourness, bitterness, sharpness, pungency More Synonyms of acid

4. graded adjective

An acid remark, or acid humour, is very unkind or critical.

This comedy of contemporary manners is told with compassion and acid humour.

Synonyms: sharp, cutting, biting, severe More Synonyms of acid

acidly graded adverb [usually ADVERB with verb, also ADVERB adjective]

'You don't know how to be a mother and you never did,' she said acidly.

Synonyms: sharply, cuttingly, bitterly, harshly More Synonyms of acid

5. uncountable noun

The drug LSD is sometimes referred to as acid.

[informal]

More Synonyms of acid

Video: pronunciation of 'acid'

Word Frequency

acid in British

(ˈæsɪd )

noun

any substance that dissociates in water to yield a sour corrosive solution containing hydrogen ions, having a pH of less than 7, and turning litmus red

acid in American

(ˈæsɪd ; asˈid)

adjective

sharp and biting to the taste; sour; tart

sharp or sarcastic in temperament or speech

that is, or has the properties of, an acid

having too heavy a concentration of acid

noun

a sour substance

6. Slang

LSD

7. Chemistry

any compound that can react with a base to form a salt, the hydrogen of the acid being replaced by a positive ion; in modern theory, any substance that produces a positive ion and accepts electrons from a base to form covalent bonds: in water solution an acid tastes sour, turns blue litmus paper red, and, in the dissociation theory, produces free hydrogen ions

Example sentences containing 'acid'

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Your other medicines ease the muscle spasm and empty acid from your stomach faster. The Sun (2016)And the one with acid rain. Times, Sunday Times (2017)The foods naturally cut acid in the body, which diseased organs fail to do. The Sun (2016)The acid test will come when we get to Germany. Times, Sunday Times (2016)When you digest a protein, essential amino acids are absorbed. Times, Sunday Times (2017)The acid test comes then. The Sun (2016)It contains an amino acid that converts into a chemical called serotonin and, apparently, an imbalance can affect your mood and sleep. The Sun (2016)Many have suffered acid or fire burns. Times, Sunday Times (2010)When acid from the stomach leaks up into the oesophagus it can lead to heartburn. The Sun (2016)This is already done when a free form amino acid capsule is taken. Chaitow, Leon The Beat Fatigue Workbook - how to identify the causes (1988)Do not boil too long with an acid food or it will not set. Smith, Drew Food Watch (1994)The soils vary from acid to basic and carry a wide range of plants. Perring, Franklyn A Guide to Britain's Conservation Heritage (1991)The muscles can get quite tight and it flushes out the lactic acid. Times, Sunday Times (2009)The process of substituting one amino acid for another in a protein is not an instantaneous one. Wills, Christopher The Runaway Brain: the Evolution of Human Uniqueness (1993)Another criticism is that the fruit sugar and acid in an apple are bad news for teeth. Times, Sunday Times (2011)This cooled the planet and caused acid rain. The Sun (2009)They tickle acid house classics in a folk style. The Sun (2011)Like somebody put acid in my drink. Times, Sunday Times (2014)Guilt burns like acid in my veins. Bachmann, Susan (editor) & Barth, Melinda Between Worlds: A Reader, Rhetoric and Handbook (1995)We all have acid in our stomachs to help digest our food. The Sun (2009)But sometimes it results from medication or bowel trouble such as excess acid or food intolerance. The Sun (2011)The next thing to explore is whether your soil is acid or alkaline. Times, Sunday Times (2008)But the acid test comes when you set the cost of servicing and repaying debts against the benefits of instant gratification. Times, Sunday Times (2006)What are its component amino acids? Times, Sunday Times (2010)We smoked weed, we dropped acid. Times, Sunday Times (2011)