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verb weak·en \ˈwē-kən\

Simple 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

Full Definition of weaken

weak·enedweak·en·ing play \ˈwēk-niŋ, ˈwē-kə-\

  1. transitive verb
  2. 1 :  to make weak :  lessen the strength of

  3. 2 :  to reduce in intensity or effectiveness

  4. intransitive verb
  5. :  to become weak

weak·en·er play \ˈwēk-nər, ˈwē-kə-\ noun

Examples of weaken

  1. The disease weakens the immune system.

  2. Some are concerned that the increase in taxes will weaken the economy.

  3. The beams had been weakened by water damage.

  4. efforts to weaken environmental laws

  5. The recent setbacks have not weakened our resolve.

  6. These kinds of contradictions weaken your argument.

  7. The disease causes the immune system to weaken.

  8. The dollar has continued to weaken against the euro.

  9. Lower interest rates have weakened the dollar.


First Known Use of weaken


Synonym Discussion of 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 an obvious and pitiable condition of 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 a usually sudden crippling or enfeebling <disabled soldiers received an immediate discharge>.

Rhymes with weaken

WEAKEN Defined for Kids


verb weak·en \ˈwē-kən\

Definition of weaken


  1. :  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>

Seen and Heard

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February 7, 2016

a slight offense

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