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Definition of know
(Entry 1 of 2)
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
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
know
nounDefinition of know (Entry 2 of 2)
in the know
: in possession of exclusive knowledge or information broadly : well-informed
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Test Your Vocabulary
A More Exception(al) Quiz
- Which of the following words is not a synonym for ‘a young person’?
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Can you spell these 10 commonly misspelled words?
TAKE THE QUIZ
Test Your Knowledge - and learn some interesting things along the way.
TAKE THE QUIZLove words? Need even more definitions?
Merriam-Webster unabridgedWords at Play
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Time Traveler for know
The first known use of know was before the 12th century
See more words from the same century