know
1 Americanverb (used with object)
-
knows,
present (3rd person singular)
-
knew,
past
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known,
past participle
-
knowing
present participle
-
to perceive or understand as fact or truth; to apprehend clearly and with certainty.
I know the situation fully.
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to have established or fixed in the mind or memory.
to know a poem by heart; Do you know the way to the park from here?
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to be cognizant or aware of.
I know it.
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be acquainted with (a thing, place, person, etc.), as by sight, experience, or report.
to know the mayor.
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to understand from experience or attainment (usually followed by how before an infinitive).
to know how to make gingerbread.
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to be able to distinguish, as one from another.
to know right from wrong.
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Archaic. to have sexual intercourse with.
verb (used without object)
-
knows,
present (3rd person singular)
-
knew,
past
-
known,
past participle
-
knowing
present participle
-
to have knowledge or clear and certain perception, as of fact or truth.
-
to be cognizant or aware, as of some fact, circumstance, or occurrence; have information, as about something.
noun
idioms
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know the ropes, to understand or be familiar with the particulars of a subject or business.
He knew the ropes better than anyone else in politics.
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in the know, possessing inside, secret, or special information.
noun
verb
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(also intr; may take a clause as object) to be or feel certain of the truth or accuracy of (a fact, etc)
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to be acquainted or familiar with
she's known him five years
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to have a familiarity or grasp of, as through study or experience
he knows French
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(also intr; may take a clause as object) to understand, be aware of, or perceive (facts, etc)
he knows the answer now
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(foll by how) to be sure or aware of (how to be or do something)
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to experience, esp deeply
to know poverty
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to be intelligent, informed, or sensible enough (to do something)
she knew not to go home yet
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(may take a clause as object) to be able to distinguish or discriminate
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archaic to have sexual intercourse with
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I have an idea
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to know how one thing or things in general work
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informal a parenthetical filler phrase used to make a pause in speaking or add slight emphasis to a statement
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things are uncertain
noun
Usage
What are other ways to say know? To know something is to perceive or understand it as fact or truth. When should you use this verb over understand or comprehend? Find out on Thesaurus.com.
Other Word Forms
Derived Forms
Inflected Forms
Participles
Conjugated Forms
Present
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knowsimple
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knowssimple
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have knownperfect
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has knownperfect
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am knowingprogressive
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are knowingprogressive
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is knowingprogressive
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have been knowingperfect progressive
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has been knowingperfect progressive
Past
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knewsimple
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had knownperfect
-
was knowingprogressive
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were knowingprogressive
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had been knowingperfect progressive
Future
Etymology
Origin of know
First recorded before 900; Middle English knowen, knawen, Old English gecnāwan; cognate with Old High German -cnāhan, Old Norse knā “to know how, be able to”; akin to Greek gignṓskein, Latin (g)nōscere, Sanskrit jñātá “known”; see also can 1, gnostic
Explanation
To know something means to have a piece of information or a certain understanding of something. If someone tells you their phone number and you remember it, you know. There's a reason you can find the word know in the word knowledge — to know is to have knowledge about something, to be familiar with an idea, or to recognize someone. If you're "in the know," you have information that is only known to a select group of people. But be careful — to know someone in the Biblical sense means that you're having sexual relations with them.
Vocabulary lists containing know
Words from "Miss Alaineus, A Vocabulary Disaster" by Debra Frasier
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Spelling Practice 1, Unit 3
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Spelling Practice, Unit 8
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
See Examples For:
Kansas has many people, "particularly in rural areas, who will not go to the hospital or see the doctor if they know they're not able to pay for it," she said.
From Barron's ● Oct. 30, 2026
In fact, he later said that he didn’t know anything about “Star Trek” until he had a meeting with the show’s creator, Gene Roddenberry, about starring in a new series: “Star Trek: The Next Generation.”
From The Wall Street Journal ● Oct. 29, 2026
"Do you know who you hurt? He is the spiritual pillar of the Chinese people," read one Weibo comment liked by more than 700 users.
From BBC ● Oct. 29, 2026
“But we’ve never experienced this. We’re all from California, you know? What’s weather?”
From Los Angeles Times ● Oct. 29, 2026
I’m pretty sure I know who left this flyer for me: the founder of Black Alliance, Zora Carter.
From "Split the Sky" by Marie Arnold
"Those players know Michael Carrick's not going to be there in two or three weeks. He knows it, they know it, everybody knows it."
From BBC ● Oct. 29, 2026
In an interview at a Panorama City campaign event last week, she pointed to her own beginnings as a young organizer, and said she knows what it’s like to go against the status quo.
From Los Angeles Times ● Oct. 29, 2026
A party for regular people, normal people, “the little guy”—one that stays in touch with them and knows what’s going on in their neighborhoods.
From The Wall Street Journal ● Oct. 29, 2026
“He’s a guy who knows how to win a purple district,” Germana had told me, and he’s calibrated his public persona and strategy around that.
From Slate ● Oct. 29, 2026
‘Who knows? But maybe -it was another kind of test? Not whether you could find the third piece of the Nanuak. But whether you could risk it for a friend.’
From "Wolf Brother" by Michelle Paver
Presland said he had been "helped by someone he knew as Kevin" - believed to be Kevin Deely, another of those Williams is accused of attempting to murder.
From BBC ● Oct. 29, 2026
By seeking out shoppers who spend around $50,000 a year on their wardrobes, and shop one of the company’s platforms 10 to 15 times in 12 months, executives knew they would lose some sales.
From The Wall Street Journal ● Oct. 29, 2026
"He knew they were going to target him in that zone. For the second time in the Test, he has fallen to the same ploy."
From BBC ● Oct. 29, 2026
Rios first claimed that Peltola knew about the gimmick before trying to retract her comments.
From Slate ● Oct. 28, 2026
I knew I should tighten my sad, limp ponytail and move on with my life, but the thing was, Sela’s hair supremacy was a new thing.
From "Legendary Frybread Drive-In" by Cynthia Leitich Smith
The director, Michael Arden, is best known for musicals, having won Tony awards for “Parade” and “Maybe Happy Ending.”
From The Wall Street Journal ● Oct. 30, 2026
Hannah, also known for his roles in Four Weddings and a Funeral, Sliding Doors and The Mummy, has been an Arsenal fan since he moved to London from Scotland more than 40 years ago.
From BBC ● Oct. 29, 2026
Picard became known for a few catchphrases including "Make it so!"
From Barron's ● Oct. 29, 2026
Besides the distinguished Starfleet officer, Stewart is also known for his portrayal of Professor Charles Xavier in the “X-Men” franchise.
From Los Angeles Times ● Oct. 29, 2026
I couldn’t tell if that meant she’d already known, that Luc had managed to give her a preview, or if it meant that she was just better than I at accepting professional news.
From "The Brightwood Code" by Monica Hesse
"The difference with Adam knowing what he was doing is that my son didn't lose his dad as a 12-year-old," he said, calling his saviour an "absolute hero, a legend".
From BBC ● Oct. 29, 2026
However, interpreting these records depends on knowing when each layer formed.
From Science Daily ● Oct. 29, 2026
It could be, for example, that the vendors worked out initial “kinks” or problems with the system, or that physicians got better at knowing what was necessary to get a case approved, she said.
From MarketWatch ● Oct. 29, 2026
But we can panic less knowing their powers are constrained.
From The Wall Street Journal ● Oct. 26, 2026
With a knowing look on her face, Hannah gives me a smile.
From "Legendary Frybread Drive-In" by Cynthia Leitich Smith
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