in·​firm in-ˈfərm How to pronounce infirm (audio)
: of poor or deteriorated vitality
especially : feeble from age
: weak of mind, will, or character : irresolute, vacillating
: not solid or stable : insecure
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 Only Holt’s third servant, an old and infirm man, lent a hand. Eric Jay Dolin, Smithsonian Magazine, 6 May 2024 Advocates say those guardians don’t have to be lawyers, as traditionally has been the case, and should include social workers and other specialists familiar with the needs of the elderly and infirm. Jake Pearson, ProPublica, 20 Mar. 2024 Our Lady of Sorrows, a hospice for infirm and dying nuns (conveniently built over ancient catacombs!), to take her vows. Jen Yamato, Washington Post, 20 Mar. 2024 Truth knew former slaves had no retirement plans and that the aged and infirm were particularly vulnerable to neglect. Cynthia Greenlee, Smithsonian Magazine, 12 Feb. 2024 The brief itself was – was legally and constitutionally infirm. Liz Cheney, CBS News, 7 Jan. 2024 Good law doesn’t withhold justice from humans who are elderly or infirm, or those who are cognitively disabled. Elizabeth Barber, The New Yorker, 16 Dec. 2023 Some were waving white flags; a few of the most elderly and infirm were pushed on rudimentary carts as Israeli troops positioned on tanks watched on. Loay Ayyoub, Washington Post, 18 Nov. 2023 Like other effects of climate change, its harms fall most heavily on those who are poor, infirm, very young or elderly. Javier Panzar, Los Angeles Times, 18 Oct. 2023

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'infirm.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


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

First Known Use

14th century, in the meaning defined at sense 1

Time Traveler
The first known use of infirm was in the 14th century

Dictionary Entries Near infirm

Cite this Entry

“Infirm.” Dictionary, Merriam-Webster, Accessed 21 May. 2024.

Kids Definition


in·​firm in-ˈfərm How to pronounce infirm (audio)
: weak or frail in body (as from age or disease)

Medical Definition


in·​firm in-ˈfərm How to pronounce infirm (audio)
: of poor or deteriorated vitality
especially : feeble from age

More from Merriam-Webster on infirm

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