acid

UK/ˈæsɪd/

acid adjective: sour, sharp, or biting to the taste; tart; having the taste of vinegar.

Image: W. Oelen, CC BY-SA 3.0, via Wikimedia Commons

Adjective

acid (comparative acider, superlative acidest)

Sour, sharp, or biting to the taste; tart; having the taste of vinegar.
- acid fruits or liquors
(figuratively) Sour-tempered.
- His response was harsh and acid.
- His voice was as stern and his face as acid as ever.1864, Anthony Trollope, The Small House at Allington, 2nd edition, volume 2, Smith, Elder & Co., page 235
Of or pertaining to an acid; acidic.
- acid soils
- Like other nyssas, it is in nature a creature of swampy places and looks loveliest where massed close to water and reflected in it, but justifies itself elsewhere if the soil is moist and acid, succeeding in wet clay.1975, Peter N. Barber, Cecil Ernest Lucas Phillips, The Trees Around Us, page 101
Denoting a musical genre that is a distortion (as if hallucinogenic) of an existing genre, as in acid house, acid jazz, acid rock.

Noun (1)

acid (countable and uncountable, plural acids)

A sour substance.
Any compound which yields H+ ions (protons) when dissolved in water; an Arrhenius acid.
- SE onset depends on a complex network of interactions among plant growth regulators, mainly auxins and cytokinins, during the proembryogenic early stages, and ethylene and gibberellic and abscisic acids later in the development of somatic embryos.2015 August 18, Clelia De-la-Peña et al., “The role of chromatin modifications in somatic embryogenesis in plants”, in Frontiers in Plant Science, volume 6, →DOI
Any compound that easily donates protons to a base; a Brønsted acid.
Any compound that can accept a pair of electrons to form a covalent bond; a Lewis acid.
Any corrosive substance.
- You are in error. / This is terror. / This is your banishment. This land is mine. / This is what you earn. / This is the Law of No Return. / This is the sour dough, this the sweet wine. / This is my history, this my race / And this unhappy man threw acid in my face.2006, James Fenton, Jerusalem
(slang, uncountable) LSD, lysergic acid diethylamide.
- In the end, though, there is one sure way to distinguish a real hippie from his assorted sympathizers: hippies drop acid. That is, real hippies frequently, if irregularly, ingest LSD.1967, Joe David Brown, editor, The Hippies, New York: Time, Inc, page 171

Noun (2) capitalized: ACID

ACID (uncountable)

(abbreviation, acronym) Acronym of atomicity, consistency, isolation, and durability, a set of properties that guarantee database transactions are processed reliably.
- SQLite relies on native file locking and page journaling to implement ACID properties.2007, Sibsankar Haldar, Inside SQLite, O'Reilly Media, →ISBN, page 31

acid meaning in Hindi, Marathi, Urdu and Bengali

acid in Hindi

sour, sharp, or biting to the taste: अम्ल amla, तेज़ाब tezāb
of or pertaining to an acid: अम्ल amla
a sour substance: अम्ल amla, एसिड esiḍ, तेज़ाब tezāb, तेजाब tejāb, तुर्शी turśī
in chemistry: तेज़ाब tezāb, अम्ल amla, तेजाब tejāb

acid in Marathi

sour, sharp, or biting to the taste: आम्ल āmla

acid in Urdu

a sour substance: تیزاب tezāb, تُرْشی turśī, ایسِڈ esiḍ
in chemistry: تیزاب tezāb, حَمْض hamz, تُرْشَہ turśa, ایسِڈ esiḍ

acid in Bengali

sour, sharp, or biting to the taste: অম্ল omlo
a sour substance: অম্ল omlo
in chemistry: অম্ল omlo

More languagesFewer languages

acid in Telugu: ఆమ్లము āmlamu
acid in Malayalam: അമ്ലം amlaṁ, ആസിഡ് āsiḍŭ
acid in Odia: ଅମ୍ଳ amḷa
acid in Sanskrit: आम्ल āmla, अम्लम् amlam, अम्ल amla
acid in Nepali: एसिड, अम्ल
acid in Pashto: تېزاب tezāb, زونځه zonjá, اسيډ asiḍ
acid in Tagalog: asido
acid in Arabic: حَامِض ḥāmiḍ, حَمْض ḥamḍ, لَاذِع lāḏiʕ, حامض ḥāmiḍ
acid in Malay: masam, berasid, asam, asid
acid in Indonesian: asam, masam
acid in Persian: اسید asid, آچار âčâr, ترش torš
acid in Thai: กรด gròt
acid in Vietnamese: chua, axit, axít, a-xít
acid in Myanmar: အက်စစ် akcac

Examples of acid in a sentence

It must be admitted that Challenger is provocative in the last degree, but Summerlee has an acid tongue, which makes matters worse.1912, Arthur Conan Doyle, The Lost World […], London; New York, N.Y.: Hodder and Stoughton, →OCLC:
She devoured with more avidity than she had her food those pretentiously phrased chronicles of the snobocracy—[…]—distilling therefrom an acid envy that robbed her napoleon of all its flavor.1914 November, Louis Joseph Vance, “An Outsider […]”, in Munsey’s Magazine, volume LIII, number II, New York, N.Y.: The Frank A[ndrew]...

All 40 example sentences with acid

Synonyms of acid

acidic

Antonyms

Forms of acid

Adjective
comparative	acider
superlative	acidest
Noun
plural	acids

Plural of acid: acids

Origin of acid

From French acide, from Latin acidus (“sour, acid”), from aceō (“to be sour”). Doublet of agita.

Phrases with acid

174 more phrasesFewer phrases

Words that rhyme with acid

28 more rhymesFewer rhymes

Questions about acid

What does acid mean?: Acid means sour, sharp, or biting to the taste; tart; having the taste of vinegar.
What is acid in Hindi?: Acid in Hindi is अम्ल (amla), तेज़ाब (tezāb), तेजाब (tejāb). See Acid meaning in Hindi.
How do you use acid in a sentence?: It must be admitted that Challenger is provocative in the last degree, but Summerlee has an acid tongue, which makes matters worse.
What part of speech is acid?: Acid can be an adjective or a noun.
How do you pronounce acid?: Acid is pronounced /ˈæsɪd/ (UK).

Words near acid in the dictionary

Adapted from Wiktionary: acid (page history and authors); ACID (page history and authors); acid (Nepali, IndicTrans2 machine translation) (model and license). Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws reformatted the entry and added links. Wiktionary data of 2026-09-02.

Last updated: 2026-09-02

Pronunciation audio from Wikimedia Commons, each file under its own free license: En-us-acid.ogg.

Cite this entry: “acid.” Word.ws, https://word.ws/acid. Based on Wiktionary, CC BY-SA 4.0.