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acidic

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Etymology and origin of the English word acidic

Confidence
Established
Formation
Derivation
First attested
1866
Ultimate origin
Latin aceō
Etymology tree
inherited borrowed derived
Latin acidus
French acide
English acid
English acidic
The word's journey

Pronunciation

  • /əˈsɪd.ɪk/[1]

Etymology

It is formed from English acid + -ic.[2][3][4][5][6] The base comes from Latin acidus (“sour, tart, sharp”), from aceō (“to be sour”),[4][2][7] from Proto-Indo-European *ak- (“to be sharp”).[4][7] The OED compares the earlier adjectives acid and acidy.[2]

Earliest recorded meaning

Merriam-Webster dates the word to 1866, in the sense "acid-forming".[5] The OED's first record is from 1868, in Dana's System of Mineralogy, of a chemical element that combines with oxygen or sulphur to form a salt with a basic element.[2]

Semantic evolution

Etymonline explains that the word began in geology, where geologists used it of the "acid" element, such as silicon, in certain salts, as the opposite of basic.[4] From 1876 it described igneous rock rich in silica.[2][3] From 1873 it meant "having the properties of an acid", later defined as having a pH below 7.[2][3] Figurative uses came in the 20th century: of speech, cutting or bitter (1936), and of colour, strikingly bright or garish (1971).[2]

Timeline

  • 1866 – acid-forming.[5] The OED's first record of this sense is from 1868.[2]
  • 1873 – chemistry, having the properties of an acid.[2]
  • 1876 – geology, of igneous rock, rich in silica.[2]
  • 1936 – of speech, cutting, bitter.[2]
  • 1971 – of colour, bright, garish.[2]

Meanings

Adjective

  1. Containing or having the properties of an acid; having a pH below 7: acidic soil.[8][5][2][3]
  2. (chemistry) Forming an acid, as an element or an oxide that yields an acid in water.[8][5][2]
  3. (geology) Of igneous rock, rich in silica.[2][3]
  4. Of remarks, sharp or biting.[2]
  5. Of colour, strikingly bright or garish.[2]

Word family

  • nonacidic
  • unacidic

References

  1. ^ Wiktionary, the free dictionary, https://en.wiktionary.org
  2. ^ a b c d e f g h i j k l m n o p q Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
  3. ^ a b c d e Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
  4. ^ a b c d Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
  5. ^ a b c d e Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
  6. ^ Dictionary.com Unabridged (2016), based on the Random House Unabridged Dictionary, New York: Random House
  7. ^ a b The American Heritage Dictionary of the English Language (online 2024), 5th ed., Boston: Houghton Mifflin Harcourt
  8. ^ a b Collins English Dictionary (2023), Glasgow: HarperCollins
Cite this entry

“Acidic.” Etymologically, 31 Oct. 2026, etymologically.com/en/acidic. Accessed 1 Nov. 2026.

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