Synonyms of weaken

weaken

verb

ˈwē-kən 

1

as in to soften

to diminish the physical strength of

weeks of hardship in the desert had greatly weakened them

Synonyms & Similar Words

• soften
• injure
• debilitate
• hurt
• enfeeble
• waste
• exhaust
• paralyze
• tire
• sap
• enervate
• damage
• impair
• cripple
• deplete
• depress
• devitalize
• incapacitate
• prostrate
• harm
• disable
• etiolate
• impoverish
• hamstring
• invalid
• grind (down)
• lay up
• wash out
• unman
• wear out
• wear down
• break down

Antonyms & Near Antonyms

• strengthen
• fortify
• recruit
• energize
• harden
• beef (up)
• invigorate
• season
• rejuvenate
• vitalize
• toughen

2

as in to fade

to lose bodily strength or vigor

the bodybuilder weakened once she eased off on her workouts

Synonyms & Similar Words

• fade
• sag
• fail
• go
• deteriorate
• sink
• wilt
• decay
• wither
• droop
• languish
• waste (away)
• lag
• emaciate
• flag
• rot
• yield
• wear out
• break down
• degenerate
• run down

Antonyms & Near Antonyms

• recover
• recuperate
• rebound
• rally
• gain
• convalesce

3

as in to dilute

to alter (something) for the worse with the addition of foreign or lower-grade substances

weakened the juice with too much water

Synonyms & Similar Words

• dilute
• infect
• cut
• pollute
• poison
• thin
• manipulate
• load
• extend
• dirty
• spoil
• adulterate
• degrade
• water down
• contaminate
• taint
• soil
• lace
• corrupt
• debase
• cheapen
• sophisticate
• defile
• misrepresent
• temper
• attenuate
• sully
• falsify
• qualify
• counterfeit
• moderate
• foul
• befoul
• tamper (with)
• spike
• envenom
• fake
• fudge
• doctor

Antonyms & Near Antonyms

• strengthen
• enrich
• fortify
• reinforce
• augment
• supplement
• fertilize
• improve
• better
• purify
• enhance
• refine
• clarify
• richen
• clean
• decontaminate
• cleanse
• purge
• flush
• leach
• filter
• distill
• lard
• concentrate
• compact
• condense
• pasteurize

Synonym Chooser

How is the word weaken distinct from other similar verbs?

Some common synonyms of weaken are cripple, debilitate, disable, enfeeble, sap, and undermine. While all these words 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

When would cripple be a good substitute for weaken?

While in some cases nearly identical to weaken, cripple implies causing a serious loss of functioning power through damaging or removing an essential part or element.

crippled by arthritis

Where would debilitate be a reasonable alternative to weaken?

The words debilitate and weaken can be used in similar contexts, but debilitate suggests a less marked or more temporary impairment of strength or vitality.

the debilitating effects of surgery

When could disable be used to replace weaken?

While the synonyms disable and weaken are close in meaning, disable suggests bringing about impairment or limitation in a physical or mental ability.

disabled by an injury sustained at work

When might enfeeble be a better fit than weaken?

The synonyms enfeeble and weaken are sometimes interchangeable, but enfeeble implies a condition of marked weakness and helplessness.

enfeebled by starvation

How are the words undermine and sap related as synonyms of weaken?

Both 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

Example Sentences

Recent Examples of weaken

Kitty Block, president and CEO of Humane World for Animals, said removing or weakening federal protections would jeopardize decades of conservation work. — Anthony Thompson, USA Today, 5 Sep. 2026

But challengers emerged and weakened its quest for dominance, often with different models ostensibly tailored to be more local. — Alexander Onukwue, semafor.com, 4 Sep. 2026

Lowell, which could target Hawaii this weekend, reached Category 5 strength Wednesday and has since weakened to Category 3. — Denise Chow, NBC news, 4 Sep. 2026

JPMorgan still expects the yen to weaken to around 160 against the dollar, as Japanese authorities seek to maintain currency stability while the BOJ continues to raise rates. — Sean Conlon,lee Ying Shan,ananya Chetia,chloe Taylor, CNBC, 3 Sep. 2026