Etymologically

unknown

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Pronunciation

  • IPA: UK /ʌnˈnəʊn/, US /ʌnˈnoʊn/[1]

Etymology

It is inherited from Middle English unknowen, formed from English un- + known, the past participle of know.[2][3] Compare Old English ungecnāwen.[2]

Earliest recorded meaning

Strange, unfamiliar, of places and persons: the 14th century in the OED,[4] about 1300 in Etymonline.[2] In the sense “ignorant of, unskilled in”, now obsolete, it is from before 1300.[4]

Semantic evolution

Of facts, not discovered or found out, is from the early 14th century (about 1330 in the OED).[2][4] The noun, an unknown person, is from the 1590s, and the unknown, that which is unknown, from the 1650s.[2] Unknown quantity was originally a term of algebra,[4] later used of a person or thing whose nature is not known.[5][6] The unknown soldier or unknown warrior is an unidentified soldier buried as a memorial to all those who died in a war.[4][6] A rare verb unknow, to fail to recognize, is from the late 14th century.[2]

Timeline

  • a. 1300 – ignorant of.[4]
  • c. 1300 – unfamiliar, of persons and places.[2]
  • c. 1330 – of facts, not known.[4]
  • 1590s – noun, an unknown person.[2]
  • 1650s – the unknown.[2]

Modern meaning

Adjective

  1. Not known or not familiar.
  2. Not identified or found out: an unknown attacker.
  3. Not famous: an unknown actor.

Noun

  1. A person who is not well known.
  2. (mathematics) A quantity whose value is not known, shown by a letter.
  3. the unknown: things or places that are not known.
  • know
  • known
  • unknowable

References

  1. ^ Jones, Daniel (2011), Cambridge English Pronouncing Dictionary, 18th ed., ed. Peter Roach, Jane Setter and John Esling, Cambridge: Cambridge University Press
  2. ^ a b c d e f g h i Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
  3. ^ Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
  4. ^ a b c d e f g Simpson, J. A.; Weiner, E. S. C., eds. (1989), The Oxford English Dictionary, 2nd ed., Oxford: Clarendon Press
  5. ^ The American Heritage Dictionary of the English Language (1992), 3rd ed., Boston: Houghton Mifflin
  6. ^ a b Collins English Dictionary (2023), Glasgow: HarperCollins