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Synonyms

illness

American  
[il-nis] / ˈɪl nɪs /

noun

  1. poor health; sickness.

    He grew up in an environment known for poverty, illness, and little opportunity for education.

  2. a specific sickness or disease, or an instance of such.

    Please be as accurate as possible in listing your childhood illnesses.

    Synonyms:
    infirmity, affliction, ailment
  3. Obsolete. wickedness.


illness British  
/ ˈɪlnɪs /

noun

  1. a disease or indisposition; sickness

  2. a state of ill health

  3. obsolete wickedness

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Usage

What does illness mean? Illness is a state of poor health or sickness, as in I’ve had to miss a lot of work due to illness.The word illness is also commonly used to refer to a disease or instance of sickness.This sense of the word is often used when the type of disease is uncertain or unknown or when someone doesn’t want to specify what it is, as in They said that he is in the hospital with an illness, but they didn’t provide any further details. The word illness is based on the adjective ill, meaning sick.Example: The best way to avoid illness is to thoroughly wash your hands.

Etymology

Origin of illness

First recorded in 1490–1500; ill + -ness

Compare meaning

How does illness compare to similar and commonly confused words? Explore the most common comparisons:

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.

"When people start moving up the weight scale, their risk of obesity-related illnesses, even in children, is increased."

From Science Daily

"Underlying or concurrent illnesses may be responsible, or the events could be coincidental," it added.

From BBC

Conan, who missed the England game because of illness, was outstanding and got his deserved try in the second half after his earlier one was chalked off.

From BBC

Others will disappear from the trail because of illness or injury.

From Los Angeles Times

The Metropolitan State Hospital opened in Norwalk in 1916, a self-contained facility complete with its own farm that treated people with mental illness.

From Los Angeles Times