Word
known
US/ˈnoʊn/
UK/nˈəʊn/
Definitions
01past participle of know
A1 · Beginner
v. the form of 'know' used with 'have' or 'be'.
v. the past participle of the irregular verb 'know'.
“I have known my best friend since we were five years old.”
“The true extent of the damage will not be known until the inspectors can safely enter the building.”
Usage
As an irregular past participle, it is used in perfect tenses and the passive voice.
02familiar or recognized
A2 · Elementary
adj. familiar to people or easy to recognize.
adj. recognized, familiar, or established through experience or observation.
“It is a known fact that smoking is bad for your health.”
“The software has several known bugs that the developers are working to fix in the next update.”
Synonyms
Antonyms
03famous for something
B1 · Intermediate
adj. famous or well-regarded for a specific reason.
adj. widely recognized or famous, often followed by 'as' or 'for'.
“The city is known for its beautiful parks and old buildings.”
“The professor is well known for her groundbreaking research into renewable energy sources.”
Usage
Often used in the pattern 'known for [quality]' or 'known as [title/name]'.
Antonyms
04a fixed value
C1 · Advanced Countable noun Mathematics Technical
n. something that is already certain or a value that is already calculated.
n. a value, constant, or fact that is already determined or familiar, particularly in a mathematical or logical problem.
“In this equation, the speed of the car is a known.”
“The researcher had to separate the knowns from the variables before the simulation could produce a reliable result.”
Collocations
Common phrases and expressions where native English speakers use the word “known” in context.
Etymology
From Middle English knowen, from Old English cnāwen (past participle). Morphologically know + -n.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.
- Exam level
- CambridgeCambridgeCambridge English QualificationsThe exam suite from Cambridge University Press & Assessment, from A1 Movers up to C2 Proficiency. The benchmark names double as CEFR labels.A1 MoversIELTSIELTSInternational English Language Testing SystemThe 0–9 band test co-owned by the British Council, IDP, and Cambridge. Used for university entry, work, and migration.2.0–3.0TOEFL iBTTOEFL iBTTest of English as a Foreign Language, Internet-Based TestETS's academic English test, the standard route for US university admissions. Scored 0–120, with a 1–6 scale since 2026.1–6 scale: 1.0–1.50–23TOEICTOEICTest of English for International CommunicationETS's workplace English test, big in Japan and Korea. Listening & Reading scores 10–990 and tops out at C1.120–224
- Frequency
- Very common
- Level
- A1 · Beginner
- Updated
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