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

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Did You Know?


Attenuate ultimately comes from a combination of the Latin prefix ad-, meaning "to" or "toward," and tenuis, meaning "thin." It has been on the medical scene since the 16th century, when a health treatise recommended eating dried figs to attenuate bodily fluids. That treatment might be outmoded nowadays, but attenuate is still used in medicine to refer to procedures that weaken a pathogen or reduce the severity of a disease. Most often, though, attenuate implies that something has been reduced or weakened by physical or chemical means. You can attenuate wire by drawing it through successively smaller holes, or attenuate gold by hammering it into thin sheets. You can even attenuate the momentum of a play by including too many costume changes.

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 Once the swarm arrives, the best officials can do is deploy pesticides to attenuate the crop destruction. Matt Simon, Wired, "Africa's Huge Locust Swarms Are Growing at the Worst Time," 16 Apr. 2020 All of these can attenuate the spread of the virus. Darren Schulte, STAT, "The novel coronavirus is a serious threat. We need to prepare, not overreact," 16 Mar. 2020 While there are vaccines and medications to attenuate the repercussions of seasonal flu, there is little health care providers can currently do to mitigate Covid-19’s devastating effects. Pauline W. Chen, New York Times, "No Room at the Inn," 12 Mar. 2020 Walls and other obstructions—including but not limited to human bodies, cabinets and furniture, and appliances—will attenuate the signal further. Jim Salter, Ars Technica, "The Ars Technica semi-scientific guide to Wi-Fi Access Point placement," 23 Feb. 2020 The ride is firm but satisfying, and the structure attenuates even the biggest wheel impacts without much protest and without the basketball-bouncing sound that a C43 sends into the cabin whenever the road turns ugly. Tony Quiroga, Car and Driver, "Cadillac's New CT5-V Needs a Different Name," 25 Feb. 2020 Whoever seeks, out of benevolence or privilege, to attenuate or abolish rebellion destroys any chance of salvation for himself. Jean Genet, Harper's magazine, "Minor Threats," 6 Jan. 2020 As Matthews explained, the highest Himalayan peaks get incredibly sunny both because there's less atmosphere to attenuate the light and because of their near-equatorial latitude. Maddie Stone, Anchorage Daily News, "World’s highest weather stations reveal intense sunshine may be melting ice on Mount Everest," 13 Dec. 2019 Census undercounts of minority groups have been a historic problem, attenuating their political influence and sparking distrust about the process, and critics say the citizenship question would make the problem worse. Timothy Williams, New York Times, "What You Need to Know About the Census Citizenship Question," 27 June 2019 Recent Examples on the Web: Adjective After that, the company hopes to show that the therapy can reduce the viral load in patients and attenuate progression to full respiratory distress, which is forcing patients to be intubated and increasing the risk of death. Adam Feuerstein, STAT, "Rudy Giuliani wants FDA to fast-track a stem cell therapy for Covid-19; critics see political meddling," 31 Mar. 2020

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.

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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

Time Traveler

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

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Last Updated

2 May 2020

Cite this Entry

“Attenuate.” Dictionary, Merriam-Webster, Accessed 29 May. 2020.

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More Definitions for attenuate


How to pronounce attenuate (audio) How to pronounce attenuate (audio)

English Language Learners Definition of attenuate

formal : to make (something) weaker or less in amount, effect, or force


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

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More from Merriam-Webster on attenuate

Thesaurus: All synonyms and antonyms for attenuate

Rhyming Dictionary: Words that rhyme with attenuate

Britannica English: Translation of attenuate for Arabic Speakers

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