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.

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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

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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.

Example Sentences

First identified in 1976 and believed to have originated in bats, Ebola is a deadly viral disease spread through direct contact with bodily fluids.

From Barron's • May 19, 2026

That previous trial showed that a Mediterranean diet enriched with extra virgin olive oil or nuts reduced cardiovascular disease risk by 30%.

From Science Daily • May 19, 2026

Ebola is a rare but deadly disease caused by a virus.

From BBC • May 18, 2026

Ebola, a viral disease with no known cure, spreads when someone comes into contact with blood or body fluids from an infected person.

From The Wall Street Journal • May 18, 2026

Multiple recurrences of the disease kept his heart weak and his health precarious.

From "American Spirits" by Barb Rosenstock

Related Words

• Cancer
• bug
• condition
• contamination
• defect
• disorder
• epidemic
• fever
• flu
• illness
• infection
• inflammation
• malady
• plague
• sickness
• stroke
• syndrome
• virus