\ˈnō \
knew\ˈnü also ˈnyü \; known\ˈnōn \; knowing

Definition of know 

(Entry 1 of 2)

transitive verb

1a(1) : to perceive directly : have direct cognition of

(2) : to have understanding of importance of knowing oneself

(3) : to recognize the nature of : discern

b(1) : to recognize as being the same as something previously known

(2) : to be acquainted or familiar with

(3) : to have experience of

2a : to be aware of the truth or factuality of : be convinced or certain of

b : to have a practical understanding of knows how to write

3 archaic : to have sexual intercourse with

intransitive verb

1 : to have knowledge

2 : to be or become cognizant sometimes used interjectionally with you especially as a filler in informal speech

know from

: to have knowledge of didn't know from sibling rivalry— Penny Marshall



Definition of know (Entry 2 of 2)

in the know

: in possession of exclusive knowledge or information broadly : well-informed

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Other Words from know


knowable \ˈnō-​ə-​bəl \ adjective
knower \ˈnō-​ər \ noun

Synonyms for know

Synonyms: Verb

comprehend, grasp, understand

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Examples of know in a Sentence


He knows a lot about the history of the town. Do you know the answer? I don't know her name. Do you know what time it is? I don't know the words to that song. They knew a good deal about the problem. She knows the rules of the game. If you want the answer, ask someone who knows. I don't know much about art, but I know what I like. She knows that many people will not believe her.
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Recent Examples on the Web: Verb

Experts don’t know why this affects some people and not others and have found that simply continuing with antibiotic treatment can do more harm to a person’s system than good, according to the National Institute of Allergy and Infectious Diseases. Kate Sheridan, SELF, "Here’s Exactly What to Do if a Tick Bites You," 14 July 2018 Today, Kardashian West is known for switching up her hair often, wearing butt-length extensions and wigs in lots of different colors and styles. Lindsey V Thompson, Allure, "Kim Kardashian West Shares a Throwback Picture Minus Her Hair Extensions and Fake Lashes," 13 July 2018 That ruling overturned the 2015 decision by the state labor board, formally known as the Public Employment Relations Board. David Garrick,, "If state Supreme Court rules against San Diego on pensions, it could could cost city millions," 14 July 2018 The home, known as the house on bluff, also has high tech features. David Gleisner, Daily Southtown, "Rare glass house carved into hillside hits the market in Olympia Fields," 14 July 2018 Their cell membranes, for example, are made up of two different kinds of fatty molecules, known as lipids. Prachi Patel, Scientific American, "Engineered Microbe Shakes Up the Tree of Life," 13 July 2018 The Armenian Shadow Puppet Theater, known as Karagyoz, was especially popular in the 18th century. Allison Keyes, Smithsonian, "Illuminating the Shadowy Art of Armenian Puppet Theater," 13 July 2018 World Peace, formerly known as Ron Artest, was ejected 11 times during his 17 year NBA career. Joseph Spears, Indianapolis Star, "Metta World Peace ejected from game after punting the ball into the crowd," 13 July 2018 The 52-year-old site, officially known as Monarch Hill Renewable Energy Park, is inching toward being full. Anne Geggis,, "Mount Trashmore, the landfill that's over 20 stories, will grow bigger and taller," 13 July 2018

Recent Examples on the Web: Noun

The operational know-how, the team, the talent, the technology infrastructure. Eric Johnson, Recode, "Grab wants to go way beyond ride-hailing in Asia, co-founder Hooi Ling Tan says," 1 Aug. 2018 Some in the know go to extreme lengths to get a head start on the bargains. Dominic Gates, The Seattle Times, "Fun, silly and fabulous at the Goodwill Glitter Sale," 10 Nov. 2018 Flamel was a deep background character in Rowling’s Harry Potter novels, and his arrival here seems both inevitable and like an in-joke for readers in the know. Tasha Robinson, The Verge, "Even for the Harry Potter hardcore, Crimes of Grindelwald is one convoluted movie," 8 Nov. 2018 Sign up here to subscribe to be in the know on holiday deals. Jolie Peters, House Beautiful, "Here's Everything You Can Expect From Amazon's 2018 Black Friday Deals," 4 Oct. 2018 Stay in the know on issues effecting women with our weekly women in the news roundup. Emily Cassidy /, NBC News, "In the Know: Women in the news," 6 July 2018 From understanding your body’s cycles to the hormones most commonly associated with women’s health, here experts discuss the must-know information and tips for a lifestyle that promotes tip-top hormonal balance. Lauren Valenti, Vogue, "Why Every 20-Something Should Know More About Their Hormones—and Their Body," 25 Oct. 2018 After months of preparation and another family wedding, this morning Princess Eugenie of York and Jack Brooksbank finally officially tied the know at St. George's Chapel in Windsor. Hanna Howard, Teen Vogue, "Princess Eugenie’s Royal Wedding Recap," 12 Oct. 2018 Its trading partners complain that Beijing's initiatives to create global competitors in fields from biotech to robots to electric cars are built on know-how the Chinese government has stolen or pressured foreign companies to hand over. Joe Mcdonald, The Christian Science Monitor, "US tariffs could spur tech development in China," 5 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'know.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of know


before the 12th century, in the meaning defined at transitive sense 1a(1)


1592, in the meaning defined above

History and Etymology for know


Middle English, from Old English cnāwan; akin to Old High German bichnāan to recognize, Latin gnoscere, noscere to come to know, Greek gignōskein


see know entry 1

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Statistics for know

Last Updated

28 Oct 2018

Look-up Popularity

Time Traveler for know

The first known use of know was before the 12th century

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More Definitions for know


\ˈnō \
knew\ˈnü, ˈnyü \; known\ˈnōn \; knowing

Kids Definition of know

1 : to recognize the identity of I know that guy!

2 : to be aware of the truth of We know that the earth is round.

3 : to have a practical understanding of Her little sister already knows how to read.

4 : to have information or knowledge He knows all about cars.

5 : to be or become aware The president knew about the problem.

6 : to be acquainted or familiar with A taxi driver knows the city well.

7 : to have understanding of It's important to know yourself. I don't know why this happens.

8 : to recognize the nature of We knew them to be honest.

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More from Merriam-Webster on know

Thesaurus: All synonyms and antonyms for know

Spanish Central: Translation of know

Nglish: Translation of know for Spanish Speakers

Britannica English: Translation of know for Arabic Speakers

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