Synonyms of infirm
1
: of poor or deteriorated vitality
especially : feeble from age
2
: weak of mind, will, or character : irresolute, vacillating
infirm in purpose
3
: not solid or stable : insecure
the infirm state of the barn
infirmly adverb
Choose the Right Synonym for infirm

weak, feeble, frail, fragile, infirm, decrepit 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

feeble suggests extreme weakness inviting pity or contempt.

a feeble attempt to walk

frail implies delicacy and slightness of constitution or structure.

a frail teenager unable to enjoy sports

fragile suggests frailty and brittleness unable to resist rough usage.

a reclusive poet too fragile for the rigors of this world

infirm suggests instability, unsoundness, and insecurity due to old age or disabling illness.

infirm residents requiring constant care

decrepit implies being worn-out or broken-down from long use or old age.

the dowager's decrepit retainers

Examples of infirm in a Sentence

The clinic provides free care for elderly and infirm people who lack health insurance. the elderly and infirm have to be especially careful during the winter months
Recent Examples on the Web
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.
The public and police are encouraged to check on the elderly and infirm. Cory Franklin, Chicago Tribune, 13 July 2025 Many of those deaths are of infirm inmates who were transferred to the state’s prison hospital in Raleigh for care and died there, records show. Charlotte Observer, 4 Aug. 2025 For the elderly or infirm, these displays could show electrocardiogram waveforms, collecting the data from wireless electrodes placed elsewhere on the body. IEEE Spectrum, 27 May 2021 The victim of the offense was a person with a disability and the defendant knew or should have known that the victim was a person with a disability or mentally or physically infirm. IndyStar, 6 Oct. 2025 See All Example Sentences for infirm

Word History

Etymology

Middle English, from Latin infirmus, from in- + firmus firm

First Known Use

1608, in the meaning defined at sense 1

Time Traveler
The first known use of infirm was in 1608

Browse Nearby Words

Cite this Entry

“Infirm.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/infirm. Accessed 8 Jul. 2026.

Kids Definition

infirm

adjective
: weak or frail in body (as from age or disease)

Medical Definition

infirm

adjective
: of poor or deteriorated vitality
especially : feeble from age

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