WEAK Synonyms: 289 Similar and Opposite Words

Q: How does the adjective 'weak' contrast with its synonyms?

Some common synonyms of weak are decrepit , feeble , fragile , frail , and infirm . While all these words mean "not strong enough to endure strain, pressure, or strenuous effort," weak applies to deficiency or inferiority in strength or power of any sort. // felt weak after the surgery

Q: When is it sensible to use 'decrepit' instead of 'weak'?

The synonyms decrepit and weak are sometimes interchangeable, but decrepit implies being worn-out or broken-down from long use or old age. // the dowager's decrepit retainers

Q: In what contexts can 'feeble' take the place of 'weak'?

Although the words feeble and weak have much in common, feeble suggests extreme weakness inviting pity or contempt. // a feeble attempt to walk

Q: When might 'fragile' be a better fit than 'weak'?

While in some cases nearly identical to weak , fragile suggests frailty and brittleness unable to resist rough usage. // a reclusive poet too fragile for the rigors of this world

Q: When is 'frail' a more appropriate choice than 'weak'?

The meanings of frail and weak largely overlap; however, frail implies delicacy and slightness of constitution or structure. // a frail teenager unable to enjoy sports

Q: Where would 'infirm' be a reasonable alternative to 'weak'?

The words infirm and weak are synonyms, but do differ in nuance. Specifically, infirm suggests instability, unsoundness, and insecurity due to old age or crippling illness. // infirm residents requiring constant care

weak

adjective

ˈwēk

Definition of weak next

as in weakened

lacking bodily strength the little boy was simply too weak to lift the box

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Antonyms & Near Antonyms

as in soft

lacking strength of will or character I was too weak to resist the free doughnuts in the office break room

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as in thin

not containing very much of some important element the coffee came out too weak because I didn't use enough ground beans

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as in unreasonable

not using or following good reasoning your argument is weak

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as in helpless

unable to act or achieve one's purpose the vice president is a relatively weak official

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Synonym Chooser

How does the adjective weak contrast with its synonyms?

Some common synonyms of weak are decrepit, feeble, fragile, frail, and infirm. While all these words mean "not strong enough to endure strain, pressure, or strenuous effort," weak applies to deficiency or inferiority in strength or power of any sort.

felt weak after the surgery

When is it sensible to use decrepit instead of weak?

The synonyms decrepit and weak are sometimes interchangeable, but decrepit implies being worn-out or broken-down from long use or old age.

the dowager's decrepit retainers

In what contexts can feeble take the place of weak?

Although the words feeble and weak have much in common, feeble suggests extreme weakness inviting pity or contempt.

a feeble attempt to walk

When might fragile be a better fit than weak?

While in some cases nearly identical to weak, fragile suggests frailty and brittleness unable to resist rough usage.

a reclusive poet too fragile for the rigors of this world

When is frail a more appropriate choice than weak?

The meanings of frail and weak largely overlap; however, frail implies delicacy and slightness of constitution or structure.

a frail teenager unable to enjoy sports

Where would infirm be a reasonable alternative to weak?

The words infirm and weak are synonyms, but do differ in nuance. Specifically, infirm suggests instability, unsoundness, and insecurity due to old age or crippling illness.

infirm residents requiring constant care

Example Sentences

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.

Recent Examples of weak Choose a soilless mix instead of standard potting soil mixes, particularly those that contain fertilizer, which cause weak, rapid growth. —

Barbara Gillette, The Spruce, 27 Feb. 2026 Looking ahead, rain and lightning storm activity will increase Friday afternoon and into Saturday ahead of a weak front. —

Garfield Hylton, The Orlando Sentinel, 27 Feb. 2026 Laggards Palo Alto Networks down 18% CrowdStrike down 16% The Club’s two weakest stocks for the month were our cybersecurity names. —

Morgan Chittum, CNBC, 27 Feb. 2026 Despite how abject all this sounds, the protagonist does not seem weak or worthy of pity. —

Hanif Abdurraqib, New Yorker, 27 Feb. 2026 See All Example Sentences for weak

Recent Examples of Synonyms for weak

Adjective

While most people recover fairly quickly from HMPV, people with weakened immune system or other medical conditions, or who are very young or old, are more likely to suffer serious illness, the Mayo Clinic said.

— Don Sweeney, Sacbee.com, 3 Mar. 2026
This type of infection is more serious for newborns, adults over 65 and those with weakened immune systems.

— Rebecca Cohen, NBC news, 26 Feb. 2026

Definition of weakened

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waywardness

weak

weaken

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“Weak.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/weak. Accessed 6 Mar. 2026.

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Last Updated: 5 Mar 2026 - Updated example sentences

Synonyms of weak

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