infirm
Americanadjective
-
feeble or weak in body or health, especially because of age; ailing.
- Synonyms:
- weak
- Antonyms:
- strong
-
unsteadfast, faltering, or irresolute, as persons or the mind; vacillating.
infirm of purpose.
- Synonyms:
- indecisive
- Antonyms:
- strong
-
not firm, solid, or strong.
an infirm support.
- Antonyms:
- strong
-
unsound or invalid, as an argument or a property title.
- Synonyms:
- weak
verb (used with object)
adjective
-
-
weak in health or body, esp from old age
-
( as collective noun; preceded by the )
the infirm
-
-
lacking moral certainty; indecisive or irresolute
-
not stable, sound, or secure
an infirm structure
an infirm claim
-
law (of a law, custom, etc) lacking legal force; invalid
Other Word Forms
Etymology
Origin of infirm
1325–75; Middle English infirme < Latin infirmus. See in- 3, firm 1
Explanation
To be infirm is to be physically weak. If your great grandmother can't get around without a walker or a wheelchair, you might describe her as infirm. The adjective infirm is most often used to talk about elderly people whose bodies don't work as well as they used to — there's an implication of old age in the word. You could also describe an infirm person as decrepit or feeble. Sometimes a person's morals or character are described as infirm, which means you can't count on them to do the right thing. The Latin root, infirmus means "weak or feeble," or alternately, "superstitious or inconstant."
Vocabulary lists containing infirm
Things Fall Apart
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Negatives with "in"
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Feeling Faint: Synonyms for "Weak"
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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.
You are buying peace of mind and financial support if you become infirm.
From MarketWatch ● Jun. 1, 2026
Humanoid robots could assist the elderly or infirm.
From The Wall Street Journal ● Oct. 8, 2025
The next morning she took him to see their infirm mother, who whispered in his ear: “I didn’t think you’d ever come back.”
From Los Angeles Times ● Aug. 28, 2025
Staples literally got the sick and infirm to stand up.
From Salon ● Jun. 17, 2025
Walter sat in a common room with older, heavily medicated people watching TV It was jarring to see him sitting in a hospital gown among people so compromised and infirm.
From "Just Mercy" by Bryan Stevenson
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.
