Merriam-Webster Logo
SINCE 1828
Menu
dictionary thesaurus

acid radical

noun

Definition of acid radical

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

There's more!

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!
Already a subscriber? Log in.

First Known Use of acid radical

1788

in the meaning defined at sense 1

See Words from the same year
NEW! Time Traveler

Seen and Heard

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

show hide

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

nonchalant

play

having an air of easy unconcern

Get Word of the Day daily email!

TRENDING NOW

  1. probity 'adherence to the highest principles and ideals'

  2. sequacious 'intellectually servile'

  3. inadmissible 'not capable of being allowed'

  4. oligarch, pejorative 'a member a government in which a small group exercises control especially for corrupt and selfish purposes'

  5. emolument 'the returns arising from office or employment usually in the form of compensation or perquisites'

SEE ALL

BROWSE DICTIONARY

acid radical

Test Your Vocabulary

The Eponym Quiz

  • rubens-painting
  • Which is the best synonym of bowdlerize?
How Strong Is Your Vocabulary?

Test your vocabulary with our 10-question quiz!

TAKE THE QUIZ
Word Winder's CrossWinder

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

TAKE THE QUIZ

Love words? Need even more definitions?

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

Words at Play

Ask the Editors

Word Games