infirmity

noun

in·​fir·​mi·​ty in-ˈfər-mə-tē 

plural infirmities

1

a

: the quality or state of being infirm

b

: the condition of being feeble : frailty

2

: disease, malady

3

: a personal failing : foible

One of the besetting infirmities of living creatures is egotism.

—A. J. Toynbee

Synonyms of infirmity

• disease
• illness
• ailment
• ill
• sickness
• condition

Examples of infirmity in a Sentence

In recent years she has had to reduce her schedule because of age and infirmity.

the infirmities of old age

Recent Examples on the Web

Colette, Mark Twain, and William Wordsworth all wrote habitually from bed, for reasons having to do with infirmity, comfort, and warding off distraction; Frida Kahlo painted self-portraits from bed, including the dreams that transcended her physical confinement. —Literary Hub, 21 Apr. 2026

Miami-Dade State Attorney Katherine Fernandez Rundle said protecting elderly people from predators who take advantage of their mental or physical infirmities is a priority of her office. —Carol Marbin Miller, Miami Herald, 16 Apr. 2026

Because of his infirmities, he is housed in a medical unit of the jail, away from the general population. —Maer Roshan, HollywoodReporter, 10 Mar. 2026

Those are the words Dr. James Parkinson used in an essay more than 200 years ago to group together symptoms and describe a mysterious infirmity afflicting six individuals in London. —Andrea Kane, CNN Money, 9 Dec. 2025

Word History

First Known Use

14th century, in the meaning defined at sense 1a

Kids Definition

infirmity

noun

in·​fir·​mi·​ty in-ˈfər-mət-ē 

plural infirmities

1

: the quality or state of being infirm

2

: ailment, disease

Medical Definition

infirmity

noun

in·​fir·​mi·​ty in-ˈfər-mət-ē 

plural infirmities

: the quality or state of being infirm

especially : an unsound, unhealthy, or debilitated state