diphtheria

noun

diph·​the·​ria dif-ˈthir-ē-ə 

nonstandard

dip- 

: an acute febrile contagious disease typically marked by the formation of a false membrane especially in the throat and caused by a gram-positive bacterium (Corynebacterium diphtheriae) that produces a toxin causing inflammation of the heart and nervous system

diphtherial

dif-ˈthir-ē-əl 

nonstandard dip-

adjective

diphtheritic

ˌdif-thə-ˈri-tik 

nonstandard ˌdip-

adjective

Examples of diphtheria in a Sentence

Recent Examples on the Web

State law still would require vaccines for polio, measles, mumps, rubella, diphtheria, pertussis and tetanus. —Cindy Krischer Goodman, The Orlando Sentinel, 16 Apr. 2026

Common examples include DTaP – for diphtheria, tetanus and pertussis – and MMR, for measles, mumps and rubella. —Kar-Hai Chu, The Conversation, 10 Apr. 2026

These bacteria are known to cause a host of ailments, including listeriosis, typhoid fever, tuberculosis, diphtheria, Guillain-Barré syndrome, miscarriage, brucellosis, chronic inflammatory conditions, reactive arthritis and death. —Mary Walrath-Holdridge, USA Today, 27 Mar. 2026

That same year, an outbreak of diphtheria began in Western Europe, its largest rise in cases in 70 years. —Patricia Callahan, ProPublica, 19 Mar. 2026

Word History

Etymology

New Latin, from French diphthérie, from Greek diphthera leather; from the toughness of the false membrane

First Known Use

circa 1851, in the meaning defined above

Rhymes for diphtheria

• arteria
• bacteria
• criteria
• egeria
• listeria
• neisseria
• wisteria
• cafeteria
• cyanobacteria
• mycobacteria

Kids Definition

diphtheria

noun

diph·​the·​ria dif-ˈthir-ē-ə  dip- 

: a contagious bacterial disease with fever in which the air passages become coated with a membranous layer that often obstructs breathing

diphtheritic

ˌdif-thə-ˈrit-ik 

ˌdip-

adjective

Medical Definition

diphtheria

noun

diph·​the·​ria dif-ˈthir-ē-ə  dip- 

: an acute febrile contagious disease typically marked by the formation of a false membrane especially in the throat and caused by a bacterium of the genus Corynebacterium (C. diphtheriae) which produces a toxin causing inflammation of the heart and nervous system

diphtherial

-ē-əl 

adjective