weaken
Americanverb (used with object)
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- Synonyms:
- invalidate, minimize, impair, reduce, lower, diminish, lessen, deplete, exhaust, sap, undermine, enervate, debilitate, enfeeble
- Antonyms:
- strengthen
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Phonetics. to change (a speech sound) to an articulation requiring less effort, as from geminate to nongeminate or from stop to fricative.
verb (used without object)
verb
Other Word Forms
Etymology
Origin of weaken
Explanation
To weaken is to become less powerful or strong. When a storm weakens, the wind dies down and the torrential rain becomes a light drizzle. If you weaken physically, your strength diminishes: "I did great at the start of the obstacle course, but my arms began to weaken toward the end and I couldn't climb that last wall." You can also weaken in resolve or spirit, like when your sister's criticism of your art project weakens your confidence about including it in an exhibition. This verb comes from weak and its Germanic root meaning "yield" or "soft."
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
Over time, that energy shortage could weaken communication in the brain and contribute to memory and thinking problems.
From Science Daily • May 16, 2026
The iShares Russell 2000 ETF trades just 2% below its 52-week high, but momentum indicators are beginning to weaken here as well.
From Barron's • May 15, 2026
The dollar strengthened, but is likely to weaken this year even if the Federal Reserve refrains from cutting interest rates, TD Securities strategists said.
From The Wall Street Journal • May 14, 2026
Plans to weaken that link are in the bill, along with measures to speed up the building of energy infrastructure to get new renewables connected to the grid more quickly by fast-tracking planning.
From BBC • May 13, 2026
With an eighth of a mile to go, Richardson felt Ligaroti beginning to weaken.
From "Seabiscuit: An American Legend" by Laura Hillenbrand
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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.