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.
There will be a seventh bell-tolling this year, for the thousands who have since died by suicide, or from cancer and other illnesses caused by the ravages of terrorism. — Jill Lepore, New Yorker, 6 Sep. 2026 With physical illness, there is usually no dispute among physicians as to its existence or non-existence. — Richard E. Vatz, Baltimore Sun, 6 Sep. 2026 While not all mosquitoes carry an illness, getting bitten is not ideal. — Elena Tittel, Chicago Tribune, 6 Sep. 2026 Eight years, 29 medications and 40 doctors later, his illness was declared treatment-resistant. — Kelly Rogers Victor, USA Today, 6 Sep. 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 7 Sep. 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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