diphtheria

American  

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

noun

Pathology.

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.

---

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

---

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.

---

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.

---

Discover More

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

Other Word Forms

• diphtherial adjective
• diphtheroid adjective

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

In 1962, President Kennedy signed the Vaccination Assistance Act, which ensured that all children under five, regardless of income, could receive vaccines against polio, diphtheria, whooping cough and tetanus.

From Salon • Jan. 4, 2026

Outbreaks of measles, diphtheria and severe diarrhea are afflicting more children and taking place more frequently because of a drop in vaccinations, health officials in Somalia’s southwest state said.

From The Wall Street Journal • Dec. 4, 2025

As early as 2 months old, babies get the first in a series of DTaP shots, which also protects against diphtheria and tetanus.

From Los Angeles Times • May 2, 2025

Weeks later, Hussein Haseeb Ahmed, 31, died in hospital after seemingly contracting diphtheria at the centre, although it was not established if that was the cause of his death.

From BBC • Apr. 7, 2025

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