weak·​en | \ ˈwē-kən How to pronounce weaken (audio) \
weakened; weakening\ ˈwēk-​niŋ How to pronounce weakening (audio) , ˈwē-​kə-​ \

Definition of weaken

transitive verb

1 : to make weak : lessen the strength of
2 : to reduce in intensity or effectiveness

intransitive verb

: to become weak

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Other Words from weaken

weakener \ ˈwēk-​nər How to pronounce weakener (audio) , ˈwē-​kə-​ \ noun

Choose the Right Synonym for weaken

weaken, enfeeble, debilitate, undermine, sap, cripple, disable mean to lose or cause to lose strength or vigor. weaken may imply loss of physical strength, health, soundness, or stability or of quality, intensity, or effective power. a disease that weakens the body's defenses enfeeble implies a condition of marked weakness and helplessness. enfeebled by starvation debilitate suggests a less marked or more temporary impairment of strength or vitality. the debilitating effects of surgery undermine and sap suggest a weakening by something working surreptitiously and insidiously. a poor diet undermines your health drugs had sapped his ability to think cripple implies causing a serious loss of functioning power through damaging or removing an essential part or element. crippled by arthritis disable suggests bringing about impairment or limitation in a physical or mental ability. disabled by an injury sustained at work

Examples of weaken in a Sentence

The disease weakens the immune system. Some are concerned that the increase in taxes will weaken the economy. The beams had been weakened by water damage. efforts to weaken environmental laws The recent setbacks have not weakened our resolve. These kinds of contradictions weaken your argument. The disease causes the immune system to weaken. The dollar has continued to weaken against the euro. Lower interest rates have weakened the dollar.
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Recent Examples on the Web

Oil prices have fallen in recent weeks over concerns about a slowing global economy, weakening energy demand and increasing U.S. production, now averaging more than 12 million barrels a day, according to the Energy Department. Jordan Blum, Houston Chronicle, "Rig count falls as New Mexico surpasses Oklahoma in drilling activity," 3 July 2019 An infection in Fletcher's tooth had spread to his heart, which was already weakened by recurring issues throughout his life and an open-heart surgery in 2008. Lauren Saria, azcentral, "2 years after a coma, this Phoenix chef is back and making the burgers of his dreams," 3 July 2019 This time is also different in that the use of state police has weakened the independence of the legislature. Kyle Sammin, National Review, "Oregon Democrats Outsource Their Duty to Drag Republicans Back to the Legislature," 28 June 2019 Facebook had pressured them to make more money from WhatsApp users, even at the cost of weakening the service’s encryption. Xavier Harding, Fortune, "WhatsApp's Latest Test Brings It and Facebook Even Closer Together," 27 June 2019 Another potential explanation is that a decline in trade union membership has weakened American workers’ bargaining power—except that unionisation rates in France and America are not far apart. The Economist, "The American exception," 27 June 2019 England comfortably beat Japan 3-0 when the sides last met in the SheBelieves Cup earlier this year, but both sides were somewhat weakened by experimentation and rotation. SI.com, "2019 Women's World Cup: 9 Mouthwatering Group Games You Must Not Miss This Summer," 6 June 2019 Vaaler said the exodus of volunteers and donors has weakened Merrill. Bob Shaw, Twin Cities, "Off-stage drama: Volunteer mutiny sparks new Woodbury theater group," 3 June 2019 Cholera is rampant among Yemenis, fueled by close living conditions, immune systems weakened by starvation, and a lack of information on prevention and treatment. Erin Blakemore, National Geographic, "In Yemen’s war, a photographer finds points of light in the darkness," 21 May 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'weaken.' 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 weaken

1530, in the meaning defined at transitive sense 1

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Statistics for weaken

Last Updated

7 Jul 2019

Look-up Popularity

Time Traveler for weaken

The first known use of weaken was in 1530

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More Definitions for weaken



English Language Learners Definition of weaken

: to make (something or someone) weaker, less forceful, less effective, etc.
: to become weaker, less forceful, less effective, etc.
of money : to decrease in value when compared to money from other countries


weak·​en | \ ˈwē-kən How to pronounce weaken (audio) \
weakened; weakening

Kids Definition of weaken

: to make or become weak or weaker … he didn't want to weaken his message by varying it one bit.— E. L. Konigsburg, Mrs. Basil E. Frankweiler

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More from Merriam-Webster on weaken

Rhyming Dictionary: Words that rhyme with weaken

Thesaurus: All synonyms and antonyms for weaken

Spanish Central: Translation of weaken

Nglish: Translation of weaken for Spanish Speakers

Britannica English: Translation of weaken for Arabic Speakers

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