illness

noun

ill·​ness ˈil-nəs How to pronounce illness (audio)
Synonyms of illnessnext
1
a
: sickness sense 2
b
: an unhealthy condition of body or mind
2
obsolete
a
: wickedness
b
: unpleasantness

Synonyms of illness

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Examples of illness in a Sentence

Her body was not able to defend itself against illness. Hundreds of soldiers died from illness and hunger. He showed no signs of illness. Scientists have not yet found a cure for this illness. cancer, diabetes, and other illnesses She died at the age of 60 after a brief illness.
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.
Documenting which children grew sickest and following an illness from house to house was a method aimed at articulating an explainable pattern. — Jim Downs, STAT, 30 Oct. 2026 Ahead of deployments or overseas tours, military families often contemplate potential life-changing events, including the death of a service member or illness of a spouse in a structured Family Contingency Plan. — Brianna Keilar, CNN Money, 30 Oct. 2026 Some developed psychological illnesses or died within a few years from physical ailments. — Jieun Baek, Foreign Affairs, 30 Oct. 2026 Research from Women Creating Change found that 21% of women cited caregiving or illness as reasons for not voting. — Sharon Sewell-Fairman, New York Daily News, 30 Oct. 2026 See All Example Sentences for illness

Word History

First Known Use

circa 1500, in the meaning defined at sense 2a

Time Traveler
The first known use of illness was circa 1500

Phrases Containing illness

Rhymes for illness

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Browse Nearby Words

ill-natured
illness
illness anxiety disorder
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Cite this Entry

“Illness.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/illness. Accessed 1 Nov. 2026.

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Kids Definition

illness

noun
ill·​ness ˈil-nəs How to pronounce illness (audio)
1
: an unhealthy condition of body or mind
2
: sickness sense 2

Medical Definition

illness

noun
ill·​ness ˈil-nəs How to pronounce illness (audio)
: an unhealthy condition of body or mind : sickness
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