Definition of diphtheria in English:

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Pronunciation: /difˈTHirēə/
Pronunciation: /dipˈTHirēə/


An acute, highly contagious bacterial disease causing inflammation of the mucous membranes, formation of a false membrane in the throat that hinders breathing and swallowing, and potentially fatal heart and nerve damage by a bacterial toxin in the blood. It is now rare in developed countries because of immunization.
  • The disease is caused by Corynebacterium diphtheriae.
Example sentences
  • Epidemics such as influenza, pneumonia, diphtheria, scarlet fever, and typhoid took a deadly toll.
  • Pasteur went on to discover vaccinations for chicken pox, cholera, diphtheria, anthrax and rabies.
  • Possible reactions to immunisation against diphtheria and tetanus and pertussis include fever, vomiting, and listlessness.


In the past, diphtheria was correctly pronounced with an f sound representing the two letters ph (as in telephone, phantom, and other ph words derived from Greek). In recent years, the pronunciation has shifted and today the more common pronunciation, no longer incorrect in standard English, is with a p sound. Nevertheless, the f sound remains the primary pronunciation.



Pronunciation: /difˈTHirēəl/
Pronunciation: /dipˈTHirēəl/
Example sentences
  • Although serious cases by skin infection are rare, it may serve as a source of diphtherial infection for spread of the organisms.
  • Corynebacterium diphtheriae is the sole member primarily pathogenic for man by virtue of its capacity to produce diphtherial exotoxin.
  • When Freundt adjuvant was used with diphtherial anatoxin (as vaccine antigen) maximum titer of induced antibodies was 1: 500 at injection introduction of vaccine in accordance with Pasteur scheme.


Pronunciation: /ˌdifTHəˈritik/ Pronunciation: /ˌdip-/
Example sentences
  • ‘In most of these occurrences, the diphtheritic form of the disease, which attacks the eyes, throats, and trachea, results in high mortality,’ Tripathy says.
  • In the diphtheritic form, there are raised, yellow plaques on the mucus membranes of the mouth and throat.
  • The results of the study suggest that diphtheritic toxin is not implicated in CNS lesions.


Mid 19th century: modern Latin, from French diphthérie (earlier diphthérite), from Greek diphthera 'skin, hide'.

Words that rhyme with diphtheria

Algeria, anterior, bacteria, Bashkiria, cafeteria, criteria, cryptomeria, exterior, hysteria, Iberia, inferior, interior, Liberia, listeria, Nigeria, posterior, Siberia, superior, ulterior, wisteria

For editors and proofreaders

Syllabification: diph·the·ri·a

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