know

Etymology

It is inherited from Middle English knowen, also knawen,^[2][3] inherited from Old English cnāwan, past tense cnēow,^[4][5][6] earlier usually gecnāwan.^[7][6] It was a strong verb of the seventh class^[4] and originally a reduplicating verb.^[7][6] It comes from Proto-Germanic *knēaną,^[1] and is related to Old High German irknāen (“to recognize”) and biknāen, which did not survive into Middle High German,^[8][5] and to Old Norse kná (“I can, I know how to”).^[8][5][7] Outside Germanic its cognates include Latin nōscō (“to get to know”) (older gnōscō), Ancient Greek γιγνώσκω (gignṓskō, “to come to know, perceive”) and Lithuanian žinóti (“to know”),^[5][9][8] all from Proto-Indo-European *gnō- (“to know”).^[4][10][5] The same root, in another form, gave English can and ken,^{[11][12][7][6]} and through Latin and Greek cognition, note, notion, agnostic and diagnosis.^[11][5] Once widespread in Germanic, the verb survives only in English.^[11][4] Hoad notes that it is absent from Dutch, Low German and Gothic, and that in Old Norse it had lost its present infinitive and meant "can".^[7] The other Germanic languages use the relatives of that verb instead, such as German kennen.^[11] Old English also had witan, the source of wit, for "to know", whose meaning partly overlapped with it.^[4][8]

Earliest recorded meaning

To recognize, to perceive a thing or person as the same as one already known: Old English, in Ælfric's Lives of Saints.^[8] Etymonline glosses the Old English verb "perceive a thing to be identical with another", and also "be able to distinguish".^[4] Barnhart finds the past tense cnēow in Beowulf (about 725) and the Middle English cnowen probably before 1200.^[5]

Semantic evolution

Know now covers ground that other languages divide between two or more verbs, such as German wissen, kennen and erkennen, or French connaître and savoir.^[4][8] In Middle English it also meant to acknowledge or confess, a sense used from about 1175 to 1579,^[8][13] and to recognize someone's authority.^[8] From the late 12th century it was used of knowing a person intimately, including sexually;^[13] Etymonline dates this sense to about 1200 and traces it to the Old Testament,^[4] and Word Origins cites the verse "And Adam knew Eve his wife; and she conceived" (Genesis 4:1).^[12] The sense "to know how to do something" appears before 1250,^[13] and "to distinguish one thing from another" about 1330.^[8] Chaucer used the verb 593 times.^[14] Johnson (1755) defined it first as "to perceive with certainty, whether intuitive or discursive".^[15] The noun know, knowledge, is recorded from 1592 and is now rare except in the phrase in the know (1883), having inside information.^[8][5][4] Phrases include as far as one knows (late 14th century), God knows (about 1400)^[4] and know the ropes (early 19th century), from the skill sailors needed in handling a ship's ropes.^[12]

Timeline

• c. 725 – past tense cnēow, in Beowulf.^[5]
• Old English – to recognize; to be acquainted with a person, place or thing; to know a fact.^[8][13]
• c. 1175 – to acknowledge or confess (obsolete after 1579); to know a person intimately, also sexually.^[13][8]
• before 1250 – to know how to do something.^[13]
• c. 1330 – to tell one thing from another.^[8]
• c. 1400 – God knows.^[4]
• 1592 – noun, knowledge.^[8][5]
• 1838 – know-how, in American English.^[5]
• 1883 – in the know.^[8][4][5]

Meanings

Verb

1. To be aware of something as a fact, or to be sure that it is true: She knew the bus would be late.^[16][17]
2. To be acquainted or familiar with a person, place or thing: They have known each other since school.^[16][2][17]
3. To have learned a subject or skill, through study or experience: He knows three languages.^[16][17]
4. To recognize, or to be able to tell apart: I'd know her handwriting anywhere.^[17][8]
5. To have experienced something: She had known hunger as a child.^[17][13]
6. (archaic) To have sexual intercourse with.^[17][13]
7. (obsolete, 1175–1579) To acknowledge or confess.^[8][6]

Noun

1. in the know: having information that most people do not have.^[8][2][6]

Word family

• knowable
• knower
• knowledge
• know-how
• unknown

Related words

• can
• ken
• cognition
• note
• notion
• agnostic
• diagnosis
• gnostic
• wit

References

1. ^ a b c Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
3. ^ Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
4. ^ a b c d e f g h i j k l Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
5. ^ a b c d e f g h i j k l Barnhart, Robert K. (1988), The Barnhart Dictionary of Etymology
6. ^ a b c d e f Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
7. ^ a b c d e Hoad, T. F., ed. (1986), The Concise Oxford Dictionary of English Etymology, Oxford: Clarendon Press
8. ^ a b c d e f g h i j k l m n o p q r Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
9. ^ Orel, Vladimir (2003), A Handbook of Germanic Etymology, Leiden / Boston: Brill
10. ^ The American Heritage Dictionary of the English Language (online 2024), 5th ed., Boston: Houghton Mifflin Harcourt
11. ^ a b c d Ayto, John (2005), Word Origins: The Secret Histories of English Words from A to Z, 2nd ed., London: A & C Black
12. ^ a b c Cresswell, Julia (2021), Oxford Dictionary of Word Origins, 3rd ed., Oxford: Oxford University Press
13. ^ a b c d e f g h Kay, Christian; Roberts, Jane; Samuels, Michael; Wotherspoon, Irené, eds. (2009), Historical Thesaurus of the Oxford English Dictionary, Oxford: Oxford University Press; online edition (2024)
14. ^ Benson, Larry D., Glossarial Concordance to Middle English (Chaucer, Gower), Johns Hopkins University, github.com/jhu-digital-manuscripts/gcme
15. ^ Johnson, Samuel (1755), A Dictionary of the English Language, London; 4th ed. 1773; Johnson's Dictionary Online, ed. Beth Rapp Young et al.
16. ^ a b c Collins English Dictionary (2023), Glasgow: HarperCollins
17. ^ a b c d e f The American Heritage Dictionary of the English Language (1992), 3rd ed., Boston: Houghton Mifflin