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

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

Other Words from weaken

weakener \ ˈwēk-​nər , ˈwē-​kə-​ How to pronounce weaken (audio) \ 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 By undertaking policies that weaken not only Syria but also its neighbors, the U.S. has ensured that Damascus remains entirely dependent on Iran and Turkey. Blaise Malley, The New Republic, 17 Nov. 2021 Some advocates have pushed for DMCA reform that would weaken or negate Section 1201's copyright protections, therefore removing the need for a triennial application process. Damon Beres, Wired, 27 Oct. 2021 Among them, Powell had multiple myeloma, a form of blood cancer that, both by itself and as a result of treatments given for the disease, can weaken the immune system. Alexander Tin, CBS News, 19 Oct. 2021 People who have a condition or are taking medications that weaken their immune system may not be fully protected even if they are fully vaccinated and have received an additional dose. Leada Gore | Lgore@al.com, al, 18 Oct. 2021 The World Health Organization considers antimicrobial resistance to be a major global threat that will weaken, kill, and send millions of people into extreme poverty within this decade. Kevin Outterson, STAT, 15 Oct. 2021 Opponents warn that the wave of legislation is an effort to take advantage of a health crisis to push an agenda that will weaken funding for public education and undermine the American promise to provide all students with a quality education. Chelsea Sheasley, The Christian Science Monitor, 7 Oct. 2021 At least 26 states have already pushed through laws that permanently weaken a governor's authority to protect public health, according to an analysis by Kaiser Health News. USA TODAY, 23 Sep. 2021 But in at least 26 states, there are now laws in place that permanently weaken the government’s ability to respond to outbreaks, according to a review by our friends at Kaiser Health News. Karen Kaplan Science And Medicine Editor, Los Angeles Times, 21 Sep. 2021

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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Dictionary Entries Near weaken

weak at/in the knees


weaker sex

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Statistics for weaken

Last Updated

22 Nov 2021

Cite this Entry

“Weaken.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/weaken. Accessed 30 Nov. 2021.

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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.
: 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, From The Mixed-up Files of Mrs. Basil E. Frankweiler

More from Merriam-Webster on weaken

Nglish: Translation of weaken for Spanish Speakers

Britannica English: Translation of weaken for Arabic Speakers


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