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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

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.

These simulations revealed clear metabolic differences between healthy individuals and those with disease, further supporting the role of these biomarkers in diagnosis.

From Science Daily • Apr. 4, 2026

Marketers also claim thymosin-alpha, one of the more studied peptides, can help with immune function, Lyme disease and COVID-19.

From Salon • Apr. 4, 2026

Excessive rainfall creating disease issues for beans limited the amount of cocoa coming out of West African ports.

From The Wall Street Journal • Apr. 3, 2026

"The effects seen on inflammatory markers made this an appealing diet to study in Crohn's disease since many patients with this disease also have elevated inflammatory markers," he said.

From Science Daily • Apr. 3, 2026

She had to fight it as well as the disease.

From "Sadako and the Thousand Paper Cranes" by Eleanor Coerr

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.