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Synonyms

disease

American  
[dih-zeez] / dɪˈziz /

noun

  1. a disordered or incorrectly functioning organ, part, structure, or system of the body resulting from the effect of genetic or developmental errors, infection, poisons, nutritional deficiency or imbalance, toxicity, or unfavorable environmental factors; illness; sickness; ailment.

    Synonyms:
    malady, disorder, infirmity, indisposition, distemper, derangement, complaint, morbidity
    Antonyms:
    health
  2. any abnormal condition in a plant that interferes with its vital physiological processes, caused by pathogenic microorganisms, parasites, unfavorable environmental, genetic, or nutritional factors, etc.

  3. any harmful, depraved, or morbid condition, as of the mind or society.

    His fascination with executions is a disease.

  4. decomposition of a material under special circumstances.

    tin disease.


verb (used with object)

diseased, diseasing
  1. to affect with disease; make ill.

    Antonyms:
    cure
disease British  
/ dɪˈziːz /

noun

  1. any impairment of normal physiological function affecting all or part of an organism, esp a specific pathological change caused by infection, stress, etc, producing characteristic symptoms; illness or sickness in general

  2. a corresponding condition in plants

  3. any situation or condition likened to this

    the disease of materialism

"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

Other Word Forms

  • diseasedly adverb
  • diseasedness noun

Etymology

Origin of disease

First recorded in 1300–50; Middle English disese, from Anglo-French dese(a)se, disaise; dis- 1 + ease

Explanation

A disease is a health condition that has a specific set of symptoms and traits — such as malaria or heart disease. Disease is not always about the human body being sick. Plants and animals are often the victims of disease. People also use the word disease in a more figurative sense to illustrate just how bad or damaging a negative influence can be — like the disease of greed among capitalists or the disease of plagiarism among college students.

Keep Reading on Vocabulary.com

Vocabulary lists containing disease

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.

A highly mutated COVID-19 strain is circulating in California — raising concerns that disease activity could rise heading into the summer.

From Los Angeles Times • Apr. 20, 2026

With their shallow root systems, addled by disease, the trees wouldn’t put up much resistance.

From Slate • Apr. 20, 2026

Citrus greening disease is caused by a bacterial infection that is delivered by the gnawing of the Asian citrus psyllid.

From Slate • Apr. 20, 2026

Gao suffers from chronic lumbar spine disease, arthritis, eye problems and chronic urticaria – a skin condition that causes itchy red welts.

From BBC • Apr. 19, 2026

Malaria was the most feared and the most prevalent disease in the Amazon.

From "Death on the River of Doubt" by Samantha Seiple