acetic acid

noun

ace·​tic acid ə-ˈsē-tik- 

: a colorless pungent liquid acid C₂H₄O₂ that is the chief acid of vinegar and that is used especially in synthesis (as of plastics)

Examples of acetic acid in a Sentence

Recent Examples on the Web

In contrast, faux sourdough may have a long ingredient list, including commercial or baker's yeast (for leavening) and tangy ingredients (like vinegar or acetic acid). —Kirsten Nunez, Martha Stewart, 13 June 2026

There are a number of products on the market that contain essential oils, like clove or citrus, sodium or ammonium derivatives or even acetic acid (vinegar). —Dawn Pettinelli, Hartford Courant, 13 June 2026

To get rid of existing clover, one option is to spray it with vinegar (acetic acid). —David Beaulieu, The Spruce, 6 June 2026

Apple Cider Vinegar Apple cider vinegar is an acetic acid made from fermenting apple juice. —Cristina Mutchler, Verywell Health, 22 May 2026

Word History

Etymology

acetic borrowed from French acétique, from Latin acētum "sour wine, vinegar" (noun derivative from *acētus, verbal adjective of acēre "to be sour," going back to Indo-European h₂eḱ-eh₁- "to be sharp") + French -ique -ic entry 1 — more at edge entry 1

First Known Use

1788, in the meaning defined above

Rhymes for acetic acid

• antacid
• placid

Kids Definition

acetic acid

noun

: a colorless strong-smelling liquid acid that gives the sour taste to vinegar and that is used especially in making chemical compounds (as plastics)

Medical Definition

acetic acid

noun

: a colorless pungent liquid acid C₂H₄O₂ that is the chief acid of vinegar and that is used especially in synthesis (as of plastics) and occasionally in medicine as an astringent and styptic