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

transitive verb

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

intransitive verb

: to become weak
ˈwē-kə- How to pronounce weaken (audio)
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

Example Sentences

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. See More
Recent Examples on the Web Instead, it is seen as part of an overall attempt to weaken an opponent’s ability and resolve to fight back, and is paired with information warfare and propaganda campaigns. Thomas Mutch, Popular Mechanics, 3 Mar. 2023 Rule number one: Never soak pearls as doing so can cause the string to weaken and break. Lauren Smith Mcdonough, Good Housekeeping, 28 Feb. 2023 Waxman seemed to get some help from justices who yesterday appeared hesitant to weaken Section 230 immunity when hearing a connected case, Gonzalez v. Google. Ashley Belanger, Ars Technica, 22 Feb. 2023 Others see it as a way to weaken the Supreme Court and attorney general – and hand the government unchecked power. Danna Harman, The Christian Science Monitor, 17 Feb. 2023 The unsavory question confronting officials at the Fed is whether the labor market will need to weaken in order to wrestle inflation lower. Jeanna Smialek, New York Times, 14 Feb. 2023 While Palestinians fear further restrictions and human-rights abuses in the occupied territories under the new government, tens of thousands of Israelis have taken to the streets to protest Netanyahu’s efforts to weaken the country’s Supreme Court. Raja Shehadeh, The New Yorker, 28 Jan. 2023 It's thought to weaken the walls of the uterus, added Dr. Kramer, putting you at risk for complications during pregnancy. Amanda Gardner, Health, 24 Jan. 2023 The whiplash between drought and flood could potentially weaken soils in some areas, which could then cause trees to fall over -- especially if they are diseased or have suffered severe fire damage, Stephenson said. Julia Jacobo, ABC News, 12 Jan. 2023 See More

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.

Word History

First Known Use

1530, in the meaning defined at transitive sense 1

Time Traveler
The first known use of weaken was in 1530

Dictionary Entries Near weaken

Cite this Entry

“Weaken.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/weaken. Accessed 24 Mar. 2023.

Kids Definition


weak·​en ˈwē-kən How to pronounce weaken (audio)
weakened; weakening ˈwēk-(ə-)niŋ How to pronounce weaken (audio)
: to make or become weak or weaker

More from Merriam-Webster on weaken

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