Quantcast
Merriam-Webster Logo
  • Dictionary
  • Thesaurus
  • Scrabble
  • Spanish Central
  • Learner's Dictionary
1

acid

play
adjective ac·id \ˈa-səd\

Simple Definition of acid

  • : of, relating to, or having the qualities of an acid

  • : sharp, strong, and critical in tone

Source: Merriam-Webster's Learner's Dictionary

Full Definition of acid

  1. 1 a :  sour, sharp, or biting to the taste <an acid flavor> b :  sharp, biting, or sour in manner, disposition, or nature <an acid individual> <an acid personality> c :  sharply clear, discerning, or pointed <an acid wit> <acid criticism> d :  piercingly intense and often jarring <acid yellow>

  2. 2 a :  of, relating to, or being an acid; also :  having the reactions or characteristics of an acid <acid soil> <an acid solution> b of salts and esters :  derived by partial exchange of replaceable hydrogen <acid sodium carbonate NaHCO3> c :  containing or involving the use of an acid (as in manufacture) <an acid bath> d :  marked by or resulting from an abnormally high concentration of acid <acid indigestion>

  3. 3 :  relating to or made by a process (as in making steel) in which the furnace is lined with acidic material and an acidic slag is used

  4. 4 :  rich in silica <acid rocks>

acidly

adverb

acidness

noun

Examples of acid in a sentence

  1. He washes his windows with an acid solution of vinegar and water.

  2. <with her acid personality, my aunt could be relied upon to bring some much-needed balance to the holiday gush>



Origin and Etymology of acid

French or Latin; French acide, from Latin acidus, from acēre to be sour — more at acet-


First Known Use: 1626

Other Chemical Engineering Terms


2

acid

noun ac·id

Simple Definition of acid

  • chemistry : a chemical with a sour taste that forms a salt when mixed with a base

Source: Merriam-Webster's Learner's Dictionary

Full Definition of acid

  1. 1 :  a sour substance; specifically :  any of various typically water-soluble and sour compounds that in solution are capable of reacting with a base to form a salt, redden litmus, and have a pH less than 7, that are hydrogen-containing molecules or ions able to give up a proton to a base, or that are substances able to accept an unshared pair of electrons from a base

  2. 2 :  something incisive, biting, or sarcastic <a social satire dripping with acid>

  3. 3 :  lsd

acidy

play \ˈa-sə-dē\ adjective

Examples of acid in a sentence

  1. the acids in your stomach

  2. the kinds of acid found in your stomach



1650

First Known Use of acid

1650

Other Chemical Engineering Terms

Rhymes with acid



ACID Defined for Kids

1

acid

play
adjective ac·id \ˈa-səd\

Definition of acid for Students

  1. 1 :  having a taste that is sour, bitter, or stinging

  2. 2 :  harsh or critical in tone <acid remarks>

  3. 3 :  of, relating to, or like an acid <an acid solution>

acidly

adverb <spoke acidly>



2

acid

play
noun ac·id

Definition of acid for Students

  1. :  a chemical compound that tastes sour and forms a water solution which turns blue litmus paper red




Medical Dictionary

1

acid

play
adjective ac·id \ˈas-əd\

Medical Definition of acid

  1. 1:  sour, sharp, or biting to the taste

  2. 2a:  of, relating to, or being an acid; also :  having the reactions or characteristics of an acid <an acid solution>bof salts and esters :  derived by partial exchange of replaceable hydrogen <acid sodium carbonate NaHCO3>c:  marked by or resulting from an abnormally high concentration of acid <acid indigestion>—not used technically




2

acid

noun ac·id

Medical Definition of acid

  1. 1:  a sour substance; specifically :  any of various typically water-soluble and sour compounds that in solution are capable of reacting with a base to form a salt, that redden litmus, that have a pH less than 7, and that are hydrogen-containing molecules or ions able to give up a proton to a base or are substances able to accept an unshared pair of electrons from a base

  2. 2:  lsd




Learn More about acid


Seen and Heard

What made you want to look up acid? Please tell us where you read or heard it (including the quote, if possible).

WORD OF THE DAY

a representation of something

Get Word of the Day daily email!

WORD GAMES

Take a 3-minute break and test your skills!

confounded-person

Which is a synonym of indolent?

philistine melancholy frenetic lazy
Name That Thing

Test your visual vocabulary with our 10-question challenge!

TAKE THE QUIZ
SCRABBLE® Sprint

Test Your Knowledge - and learn some interesting things along the way.

TAKE THE QUIZ