Etymologically
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unpredictable

This is the current revision of this entry, as edited by bogdan on 25 October 2026 at 23:42. This address is a permanent link to this version.
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Pronunciation

  • UK: /ˌʌnprɪˈdɪktəb(ə)l/, /ˌʌmprɪˈdɪktəb(ə)l/[1]
  • US: /ˌʌnprɪˈdɪktəb(ə)l/, /ˌʌnpriːˈdɪktəb(ə)l/[1]

Etymology

It is formed from English un- + predictable.[2][3][4][5] The adjective predictable, recorded from 1820, is from predict and -able,[3][2] and predict goes back to Latin praedīcō (“to say beforehand, foretell”), from prae- (“before”) and dīcō (“to say”).[2][3]

Earliest recorded meaning

Not predictable; difficult or impossible to foresee: 1840, in The Dial.[2][6][3] Dictionary.com dates the word to 1855–60.[5]

Semantic evolution

The word followed predictable by twenty years.[3][2] It was used as a noun, with the, for whatever cannot be predicted, from 1859, in Alexander Bain's The Emotions and the Will, and later also for a single unpredictable event or thing;[2][6] the Shorter Oxford dates the noun only to the mid 20th century.[4] The derivative unpredictability is recorded from the early 20th century, and unpredictably and unpredictableness from the mid 20th century.[4]

Timeline

  • 1820 – predictable.[3][2]
  • 1840 – unpredictable, adjective.[2][6][3]
  • 1859 – noun, the unpredictable.[2][6]
  • early 20th century – unpredictability.[4]

Meanings

Adjective

  1. Not able to be predicted or foreseen: The weather in the mountains is unpredictable.[6][7][8][2]
  2. Likely to change or behave in ways that cannot be foreseen; changeable.[7][8]

Noun

  1. An unpredictable person, thing or event; also, with the, whatever cannot be foreseen.[6][8][2]

Word family

  • unpredictability
  • unpredictably

References

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