measles

noun

mea·​sles ˈmē-zəlz 

plural in form but singular or plural in construction

1

a

: an acute contagious disease that is caused by a morbillivirus (species Measles morbillivirus) and is marked especially by an eruption of distinct red circular spots

called also rubeola

b

: any of various eruptive diseases (such as German measles)

2

[Middle English mesel infested with tapeworms, literally, leprous, from Anglo-French, from Medieval Latin misellus leper, from Latin, wretch, from misellus, diminutive of miser miserable] : infestation with or disease caused by larval tapeworms in the muscles and tissues

Examples of measles in a Sentence

Recent Examples on the Web

The health department is also adding measles PCR testing capability to its lab, but the process was expected to take several weeks. —Matt Leclercq, Fort Worth Star-Telegram, 1 Apr. 2025

This is up from only 35% of Americans in June of last year, in the face of rising bird flu and measles cases. —Irene Wright, Miami Herald, 1 Apr. 2025

There is still much to learn about the measles virus. —Peter Kasson, The Conversation, 31 Mar. 2025

Health and Human Services Secretary Robert F. Kennedy Jr. has touted vitamin A as a measles treatment, but the side effects of a vitamin overdose are dire. —April Rubin, Axios, 31 Mar. 2025

Word History

Etymology

Middle English meseles, plural of mesel measles, spot characteristic of measles; akin to Middle Dutch masel spot characteristic of measles

First Known Use

14th century, in the meaning defined at sense 1a

Phrases Containing measles

• German measles

Rhymes for measles

• diesels
• easels
• weasels

Kids Definition

measles

singular or plural noun

mea·​sles ˈmē-zəlz 

: a contagious disease caused by a virus and marked by fever and red spots on the skin

also : any of several diseases (as German measles) that resemble measles

Medical Definition

measles

noun, plural in form but singular or plural in construction

mea·​sles ˈmē-zəlz 

1

a

: an acute contagious disease that is caused by a paramyxovirus of the genus Morbillivirus (species Measles morbillivirus), that commences with catarrhal symptoms, conjunctivitis, cough, and Koplik's spots on the oral mucous membrane, and that is marked by the appearance on the third or fourth day of an eruption of distinct red circular spots which coalesce in a crescentic form, are slightly raised, and after the fourth day of the eruption gradually decline

called also rubeola

b

: any of various eruptive diseases (as German measles)

2

: infestation with or disease caused by larval tapeworms in the muscles and tissues

specifically : infestation of cattle and swine with cysticerci of tapeworms that as adults parasitize humans compare measle