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

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Other Words from weaken

weakener \ ˈwēk-​nər , ˈwē-​kə-​ How to pronounce weakener (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 Murray fiercely fought environmental and climate regulations, and the Trump administration has fulfilled several of his requests to roll back or weaken Obama-era controls on coal. Josh Siegel, Washington Examiner, "Daily on Energy: More signs that climate legislation would be atop Biden agenda," 26 Oct. 2020 Measures proposed by Cicilline could arm competition cops with new powers and weaken legal barriers that many say have tilted the playing field too much in favor of big companies. David Mclaughlin, Bloomberg.com, "Washington’s One-Two Antitrust Punch Is About to Smack Big Tech," 13 Oct. 2020 The lack of progress investigating retaliation follows other similar moves by the Trump Administration to slow or weaken measures intended to protect workers. Washington Post, "Labor agency investigates few complaints of retaliation against workers who raise coronavirus concerns, report finds," 8 Oct. 2020 Cooler waters immediately along the coast may help weaken Delta prior to landfall. NBC News, "Tropical Storm Delta breaks record for earliest 25th named storm," 5 Oct. 2020 In Springfield and Washington, industry supporters continue to propose legislation that would require the use of coal to generate electricity, weaken renewable energy mandates and eliminate environmental protections. Michael Hawthorne, chicagotribune.com, "Gov. J.B. Pritzker vows to fight climate change with clean energy. Only three other states mined more climate-changing coal than Illinois last year.," 2 Oct. 2020 The loss of that income is likely to weaken spending and the economy in the coming months. Arkansas Online, "U.S. layoffs remain elevated as 837,000 seek jobless aid," 1 Oct. 2020 Months of coronavirus isolation can contort your body, weaken your heart and impair the brain function. CNN, "Start your week smart: French Open, 'SNL,' presidential debate, Covid 19, wildfires," 27 Sep. 2020 Already, cases are headed to the court that would provide an opportunity to overturn or weaken Roe. Jessica Gresko, Star Tribune, "On guns, abortion, high court could become more conservative," 27 Sep. 2020

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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Time Traveler for weaken

Time Traveler

The first known use of weaken was in 1530

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Statistics for weaken

Last Updated

28 Oct 2020

Cite this Entry

“Weaken.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/weaken. Accessed 28 Oct. 2020.

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More Definitions for weaken


How to pronounce weaken (audio)

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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