adjective
known
nohn
adjective
1
Recognized or identified as a particular type of person or thing; well-established in reputation.
"He is a known troublemaker at the office."
"She is known for her honesty and hard work."
2
Familiar, understood, or already established as fact.
"Scientists studied the known effects of the drug before testing a new dose."
"There are no known cures for the common cold."
noun
1
Something that is already established or understood, as opposed to the unknown.
"The detective preferred to work from the knowns before guessing at the rest."
"In science, you build new theories on top of the knowns."
2
In mathematics, a quantity whose value has already been determined, as opposed to a variable being solved for.
"The equation had two knowns and one unknown to solve for."
"She plugged the knowns into the formula to find x."
How to Use Known
Learner’s notesIn plain EnglishAlready recognized, identified, or established as fact — the opposite of unknown.
Common mistake
As a noun ("the knowns and unknowns"), it is mainly used in science, math, and formal writing — in everyday speech people usually just say "what we know."
Common pairings
a known fact
known for
known as
well known
Word Forms
better known comparative, knowns plural, best known superlative
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Etymology
The past participle of "know," from Old English cnāwan, ultimately from a very old root meaning "to recognize" that also gave us "notice" and "note" in other languages.