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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.

But even when impacted by injury and illness, Canada still have the strongest team.

From BBC

But the teenager says her "future is on hold" after being diagnosed with a rare chronic illness that leaves her unable to sit up.

From BBC

The state law governing involuntary commitments and conservatorships for people with severe mental illness is known as the Lanterman-Petris-Short Act, and it includes the commonly used Section 5150 for those deemed “gravely disabled.”

From Los Angeles Times

Anna de Peyster, a writer, philanthropist and a former wife of Rupert Murdoch, has died following a long illness.

From The Wall Street Journal

Because these conditions are also tied to dementia, researchers have questioned whether polluted air raises Alzheimer's risk indirectly by contributing to those illnesses, or whether it harms the brain more directly.

From Science Daily