ill·​ness | \ˈil-nəs \

Definition of illness 

1a : sickness sense 2

b : an unhealthy condition of body or mind

2 obsolete

a : wickedness

b : unpleasantness

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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.
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Recent Examples on the Web

But the metabolic illness struck and sidelined him for seven months, and an erratic season this year failed to convince. Christophe Beaudufe,, "Gotze, from World Cup glory to soccer hell in four years," 13 July 2018 The illness can last between four and seven days, and in some cases severe diarrhea may cause hospitalization and in rare cases death, if not treated soon enough. Sarah Gray, Fortune, "Kellogg's Honey Smacks Cereal Linked to 100 Salmonella Infections, CDC Warns," 13 July 2018 Pseudogymnoascus destructans, a fungus that causes the fatal illness known as white-nose syndrome, has killed more than 90 percent of these bats in some parts of North America, making the nocturnal animal hard to find. Justin Wm. Moyer, Washington Post, "A mysterious disease is killing millions of bats. These scientists are trying to save them.," 12 July 2018 By McClatchy Initial symptoms are flu-like and without early treatment, the illness is almost always fatal. Andy Marso, kansascity, "After JoCo bat tests positive for rabies, health department warns residents of danger," 10 July 2018 At the time, isolation was the main way health officials dealt with the illness. Devin Kelly, Anchorage Daily News, "Meet the city health worker who tracks down tuberculosis patients in Anchorage," 3 July 2018 Out: Galaxy — D Rolf Feltscher (shoulder), M Sebastian Lletget (ankle); Revolution — D Chris Tierney (knee), M Isaac Angking (illness), F Femi Hollinger-Janzen (elbow)., "Galaxy vs. Revolution," 14 July 2018 Doctors prepared Dempsey and her fiancée, Gabriel Schultz, for the worst and that the baby didn’t have an immune system prepared to fight the illness, WTVR reported. Natalie Dreier, ajc, "Baby dies from meningitis, parents issue warning," 12 July 2018 NewsNearly wiped out by mystery illness, California starfish make... Peter Fimrite,, "Fight brewing over Privates Beach in Santa Cruz County, which charges $100 yearly fee," 12 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'illness.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of illness

circa 1500, in the meaning defined at sense 2a

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Statistics for illness

Last Updated

9 Nov 2018

Look-up Popularity

Time Traveler for illness

The first known use of illness was circa 1500

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More Definitions for illness



English Language Learners Definition of illness

: a condition of being unhealthy in your body or mind

: a specific condition that prevents your body or mind from working normally : a sickness or disease


ill·​ness | \ˈil-nəs \

Kids Definition of illness

1 : an unhealthy condition of the body or mind Germs can cause illness.

2 : a specific sickness or disease Colds are a common illness.


ill·​ness | \ˈil-nəs \

Medical Definition of illness 

: an unhealthy condition of body or mind : sickness

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Comments on illness

What made you want to look up illness? Please tell us where you read or heard it (including the quote, if possible).


playful or foolish behavior

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