acid radical

noun

1
: the negative ion (as the sulfate ion SO4−−) of an acid : anion
—now used especially by analysts
2
: a radical formed by removal of all hydroxyl or analogous groups (as mercapto) from an acid
benzoyl C6H5CO− is the acid radical corresponding to benzoic acid C6H5COOH
sulfuryl >SO2 is the acid radical of sulfuric acid H2SO4
compare acyl

Word History

First Known Use

1788, in the meaning defined at sense 1

Time Traveler
The first known use of acid radical was in 1788

Love words?

You must — there are over 200,000 words in our free online dictionary, but you are looking for one that’s only in the Merriam-Webster Unabridged Dictionary.

Start your free trial today and get unlimited access to America's largest dictionary, with:

  • More than 250,000 words that aren't in our free dictionary
  • Expanded definitions, etymologies, and usage notes
  • Advanced search features
  • Ad free!

Dictionary Entries Near acid radical

acid process

acid radical

acid rain

See More Nearby Entries 

Cite this Entry

“Acid radical.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/acid%20radical. Accessed 29 Mar. 2023.

Copy Citation

Share

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

Word of the Day

Listen to the pronunciation of immaculate

See Definitions and Examples »

Test Your Vocabulary

What Did You Just Call Me?

  • brown chihuahua sitting on the floor with squinting eyes looking at the camera
  • Before we went to her house, Hannah told us her aunt was a flibbertigibbet.
Name That Thing

You know what it looks like… but what is it called?

TAKE THE QUIZ
Solve today's spelling word game by finding as many words as you can with using just 7 letters. Longer words score more points.

Can you make 12 words with 7 letters?

PLAY
Words at Play
Ask the Editors
Word Games