diphtheria

American  

[dif-theer-ee-uh, dip-] / dɪfˈθɪər i ə, dɪp- /

noun

Pathology.

diphtherias plural

1. a febrile, infectious disease caused by the bacillus Corynebacterium diphtheriae, and characterized by the formation of a false membrane in the air passages, especially the throat.

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diphtheria British  

/ dɪf-, dɪf-, dɪpˈθɪərɪə, ˌdɪpθəˈrɪtɪk, dɪpˈθɛrɪk, dɪf- /

noun

1. an acute contagious disease caused by the bacillus Corynebacterium diphtheriae, producing fever, severe prostration, and difficulty in breathing and swallowing as the result of swelling of the throat and formation of a false membrane

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diphtheria Scientific  

/ dĭf-thîr′ē-ə,dĭp- /

1. An infectious disease caused by the bacterium Corynebacterium diphtheriae and characterized by fever, swollen glands, and the formation of a membrane in the throat that prevents breathing. Infants are routinely vaccinated against diphtheria, which was once a common cause of death in children.

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diphtheria Cultural  

1. An acute disease, and a contagious disease, caused by bacteria that invade mucous membranes in the body, especially those found in the throat. The bacteria produce toxic substances that can spread throughout the body.

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Discover More

In developed countries, diphtheria has been virtually wiped out through an active program of infant immunization.

Other Word Forms

Derived Forms

• diphtherial
  adjective
• diphtheroid
  adjective

Inflected Forms

Nouns

• diphtherias
  plural

Etymology

Origin of diphtheria

1850–55; < New Latin < French diphthérie < Greek diphthér ( a ) skin, leather + -ia -ia

Explanation

Diphtheria is a serious disease that spreads between people through sneezes and coughs. Luckily, diphtheria is easily prevented with a vaccine that's commonly given to babies. Most people who get diphtheria can expect to spend a week or so feeling pretty awful, with a cough, sore throat, and fever. For others, diphtheria is dangerous and even deadly, killing tissues in the airway and making it difficult to breathe, and sometimes damaging the heart. In most of the world, diphtheria vaccines are readily available. In Greek, the word diphtheria means "leather," a reference to the leathery coating the disease can cause in the throat.

Example Sentences

See Examples For:

diphtheria diphtherias

The twins had received vaccines for hepatitis A, influenza, and DTaP, which includes diphtheria, tetanus and pertussis vaccines, during their 18-month wellness visit at their pediatrician’s office in April 2025, according to the civil suit.

From The Wall Street Journal ● Jul. 8, 2026

The affected data include childhood immunization rates against diphtheria, tetanus, pertussis, polio, measles, mumps and rubella, hepatitis, chicken pox and flu; and rates for 13 year olds and expectant mothers.

From Los Angeles Times ● Jul. 3, 2026

"There's an increased risk now of outbreaks of vaccine-preventable diseases" such as measles and diphtheria, due to low pre-earthquake vaccination coverage, he said.

From Barron's ● Jul. 1, 2026

Australia has recorded its first diphtheria death in almost a decade as the country grapples with the worst outbreak of the vaccine-preventable disease in decades.

From BBC ● May 26, 2026

We had lobar pneumonia, meningococcal meningitis, streptococcal infections, diphtheria, endocarditis, enteric fevers, various septicemias, syphilis, and, always, everywhere, tuberculosis.

From "The Lives of a Cell" by Lewis Thomas

Answer, all ye pneumonias and diphtherias and rheumatisms!

From Manners and Social Usages by Sherwood, Mrs. John M. E. W.

There would be less diphtherias and fevers and starvation; for that's its right name, Darcy.

From Hope Mills or, Between Friend and Sweetheart by Douglas, Amanda Minnie