acid

[as-id] /ˈæs ɪd/
noun
1.
Chemistry. a compound usually having a sour taste and capable of neutralizing alkalis and reddening blue litmus paper, containing hydrogen that can be replaced by a metal or an electropositive group to form a salt, or containing an atom that can accept a pair of electrons from a base. Acids are proton donors that yield hydronium ions in water solution, or electron-pair acceptors that combine with electron-pair donors or bases.
2.
a substance with a sour taste.
3.
something, as a remark or piece of writing, that is sharp, sour, or ill-natured:
His criticism was pure acid.
4.
Slang. LSD (def 2).
adjective
5.
Chemistry.
  1. belonging or pertaining to acids or the anhydrides of acids.
  2. having only a part of the hydrogen of an acid replaced by a metal or its equivalent:
    an acid phosphate.
  3. having a pH value of less than 7.
    Compare alkaline (def 4).
6.
sharp or biting to the taste; tasting like vinegar; sour:
acid fruits.
7.
sharp, biting, or ill-natured in mood, manner, etc.:
an acid remark; an acid wit.
8.
Geology. containing much silica.
9.
Metallurgy. noting, pertaining to, or made by a process in which the lining of the furnace, or the slag that is present, functions as an acid in high-temperature reactions in taking electrons from oxide ions: usually a siliceous material, as sand or ganister.
Compare basic (def 3).
Idioms
10.
put on the acid, Australian Slang. to importune someone, as for money, sexual favors, or confidential information.
Origin
1620-30; < Latin acidus sour, akin to ācer sharp, acētum vinegar, acescent, acicula
Related forms
acidly, adverb
acidness, noun
nonacid, noun, adjective
preacid, adjective
preacidness, noun
semiacid, adjective
Can be confused
acerbic, acid, acrid.
Synonyms
7. acerbic, stinging, vitriolic, tart. Acid, astringent are terms used figuratively of wit or humor. Acid suggests a sharp, biting, or ill-natured quality: an acid joke about an opponent. Astringent connotes severity but usually also a bracing quality, as of something applied with curative intent: astringent criticism.
Examples from the web for acids
  • The fat or tallow consists of a chemical combination of fatty acids with glycerin.
  • The alpha acids in the resin contribute to the bitterness of beer.
  • Proteins are made up of amino acids, some that are attracted to water, others that are repelled by water.
  • They re-supply the body with carbohydrates, usually antioxidants and sometimes amino acids and caffeine.
  • Saturated fatty acids have rigid hydrocarbon tails while unsaturated fatty acids have bent hydrocarbon tails.
  • We've modified photosynthetic bacteria to enhance their ability to produce and excrete long-chain fatty acids.
  • Digesters do a poor job of processing long-chain fatty acids, leaving behind a thick layer of fat at the end of digestion.
  • To make proteins, the human body needs twenty different kinds of amino acids.
  • Fear of the dark is an arrangement of fifteen amino acids.
  • The proteins of barnacle glue, they discovered, are dominated by amino acids called proline and isoleucine.
British Dictionary definitions for acids

acid

/ˈæsɪd/
noun
1.
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 See also Lewis acid
2.
a sour-tasting substance
3.
a slang name for LSD
adjective
4.
(chem)
  1. of, derived from, or containing acid: an acid radical
  2. being or having the properties of an acid: sodium bicarbonate is an acid salt
5.
sharp or sour in taste
6.
cutting, sharp, or hurtful in speech, manner, etc; vitriolic; caustic
7.
(of rain, snow, etc) containing pollutant acids in solution
8.
(of igneous rocks) having a silica content of more than 60% of the total and containing at least one tenth quartz
9.
(metallurgy) of or made by a process in which the furnace or converter is lined with an acid material: acid steel
Derived Forms
acidly, adverb
acidness, noun
acidy, adjective
Word Origin
C17: (first used by Francis Bacon): from French acide or Latin acidus, from acēre to be sour or sharp
Word Origin and History for acids

acid

adj.

1620s, "of the taste of vinegar," from French acide (16c.) or directly from Latin acidus "sour, sharp," adjective of state from acere "to be sour," from PIE root *ak- "sharp, pointed" (see acrid). Figurative use from 1775; applied to intense colors from 1916. Acid test is American English, 1892, from the frontier days, when gold was distinguished from similar metals by application of nitric acid. Acid rain is first recorded 1859 in reference to England.

n.

1690s, from acid (adj.). Slang meaning "LSD-25" first recorded 1966 (see LSD).

When I was on acid I would see things that looked like beams of light, and I would hear things that sounded an awful lot like car horns. [Mitch Hedberg, 1968-2005, U.S. stand-up comic]
Acid rock (type played by or listen to by people using LSD) is also from 1966; acid house dance music style is 1988, probably from acid in the hallucinogenic sense + house "dance club DJ music style."

acids in Medicine

acid ac·id (ās'ĭd)
n.

  1. Any of a large class of sour-tasting substances whose aqueous solutions are capable of turning blue litmus indicators red, of reacting with and dissolving certain metals to form salts, and of reacting with bases or alkalis to form salts.

  2. A substance that ionizes in solution to give the positive ion of the solvent.

  3. A substance capable of yielding hydrogen ions.

  4. A proton donor.

  5. An electron acceptor.

  6. A molecule or ion that can combine with another by forming a covalent bond with two electrons of the other.

  7. A substance having a sour taste.

  8. See LSD.

adj.

  1. Of or relating to an acid.

  2. Having a high concentration of acid.

  3. Having a sour taste.

acids in Science
acid
  (ās'ĭd)   
Any of a class of compounds that form hydrogen ions when dissolved in water, and whose aqueous solutions react with bases and certain metals to form salts. Acids turn blue litmus paper red and have a pH of less than 7. Their aqueous solutions have a sour taste. Compare base.

acidic adjective
acids in Culture

acid definition


A sour-tasting material (usually in a solution) that dissolves metals and other materials. Technically, a material that produces positive ions in solution. An acid is the opposite of a base and has a pH of 0 to 7. A given amount of an acid added to the same amount of a base neutralizes the base, producing water and a salt. Common vinegar, for example, is a weak solution of acetic acid.

Note: Figuratively, acid applies to anything sour or biting; for example, an “acid wit” is sharp and unpleasant.
Slang definitions & phrases for acids

acid

modifier

: an acid party

noun

The hallucinogen LSD, which is chemically an acid; a (Narcotics)

Related Terms

battery acid


Related Abbreviations for acids

ACIDS

American College of Integrated Delivery Systems

ACID

aircraft identification