English Reference
adjective · noun

known

adj. · n.
US /ˈnoʊn/ UK /nˈəʊn/ known UK spelling knowns

  1. 01 A2 Elementary

    adj.familiar to people or easy to recognize.

    adj.familiar, recognized, or established through experience or observation.

    Simple

    It is a known fact that smoking is bad for your health.

    In context

    The patient had no known allergies to the medication, so the doctor proceeded with the standard prescription.

  2. 02 B1 Intermediate

    adj.famous or well-regarded for a specific reason.

    adj.widely recognized or famous, often followed by 'as' or 'for'.

    Simple

    The city is known for its beautiful parks and old buildings.

    In context

    The author is primarily known for her historical novels, though she has recently experimented with science fiction.

  3. 03 C1 Advanced Technical Math

    n.something that is already certain or a value that is already calculated.

    n.a fact or variable whose value or nature is already determined or established.

    Simple

    In this equation, the speed of the car is a known.

    In context

    When solving for the trajectory, we must first isolate the knowns from the variables to simplify the calculation.

Usage known to support · known evidence · known for years


From Middle English knowen, from Old English cnāwen (past participle). Morphologically know + -n.

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry
Origin Old English cnāwen
Level A1 · Beginner
Frequency Very common
Updated