at·​ten·​u·​ate | \ ə-ˈten-yə-ˌwāt How to pronounce attenuate (audio) , -yü-ˌāt How to pronounce attenuate (audio) \
attenuated; attenuating

Definition of attenuate

 (Entry 1 of 2)

transitive verb

1 : to lessen the amount, force, magnitude, or value of : weaken … shows great skill in the use of language to moderate or attenuate the impact of awkward facts.— Bernard Lewis
2 : to reduce the severity, virulence, or vitality of an attenuated virus
3 : to make thin or slender Glass can be attenuated into fibers.
4 : to make thin in consistency : rarefy attenuate oil by heating it

intransitive verb

: to become thin, fine, or less


at·​ten·​u·​ate | \ ə-ˈten-yə-wət How to pronounce attenuate (audio) , -yü-ət \

Definition of attenuate (Entry 2 of 2)

1 : reduced especially in thickness, density, or force the attenuate limbs of a starving person
2 : tapering gradually usually to a long slender point attenuate leaves

Did you know?

Attenuate ultimately comes from a combining of the Latin prefix ad-, meaning "to" or "toward," and tenuis, meaning "thin," a pedigree that is in keeping with the English word's current meanings, which all have to do with literal or metaphorical thinning. The word is most common in technical contexts, where it often implies the reduction or weakening of something by physical or chemical means. You can attenuate wire by drawing it through successively smaller holes, for example, or attenuate gold by hammering it into thin sheets. Current evidence dates the term to the 16th century, in which we find many references to bodily humors in need of being attenuated; modern medicine prefers to use the word in reference to procedures that weaken a pathogen or reduce the severity of a disease.

Examples of attenuate in a Sentence

Verb Earplugs will attenuate the loud sounds of the machinery. an investment attenuated by significant inflation over the years
Recent Examples on the Web: Verb Authorities and the private sector leadership are beginning to re-invent mechanisms to attenuate these shocks to our financial system, often hand-in-hand. Hec Paris Insights, Forbes, 1 July 2022 The program is designed to attenuate the agoraphobia, or fear of entering spaces from which escape might be difficult, that individuals with schizophrenia often feel. Raleigh Mcelvery, Smithsonian Magazine, 6 May 2022 In both cloudy and clear conditions, biologically significant red light penetrated down to less than 1 percent of the seafloor, mainly because those wavelengths attenuate faster in water than green and blue light do. Scott Hershberger, Scientific American, 14 Aug. 2020 As the state gets hotter, more and more water will evaporate away from its canals, which the panels can help attenuate. Matt Simon, Wired, 19 Mar. 2021 Time and again, the reader is reminded how various structural factors attenuate certain disparities, what this or that policy means for the most vulnerable, and so on. Patrick Blanchfield, The New Republic, 25 May 2021 Low-frequency sounds attenuate much more slowly than high-frequency sounds, like bird chirps, which travel only short distances. Taylor L. Machette, Scientific American, 4 Oct. 2020 The necessity of prudential judgment in some cases is sometimes exploited to attenuate the general obligation of solidarity. Ramesh Ponnuru, National Review, 1 Oct. 2020 If that’s the case, then hot and humid weather could attenuate the spread of the disease. Roxanne Khamsi, Wired, 18 June 2020 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'attenuate.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of attenuate


1530, in the meaning defined at transitive sense 3


15th century, in the meaning defined at sense 1

History and Etymology for attenuate

Adjective and Verb

Middle English attenuat, from Latin attenuatus, past participle of attenuare to make thin, from ad- + tenuis thin — more at thin

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Time Traveler for attenuate

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The first known use of attenuate was in the 15th century

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Last Updated

14 Jul 2022

Cite this Entry

“Attenuate.” Dictionary, Merriam-Webster, Accessed 12 Aug. 2022.

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More Definitions for attenuate


transitive verb
at·​ten·​u·​ate | \ ə-ˈten-yə-ˌwāt How to pronounce attenuate (audio) \
attenuated; attenuating

Medical Definition of attenuate

: to reduce the severity of (a disease) or virulence or vitality of (a pathogenic agent) a procedure to attenuate severe diabetes attenuated bacilli

More from Merriam-Webster on attenuate

Britannica English: Translation of attenuate for Arabic Speakers


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