Definition of measles
1a
: 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
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Merriam-Webster unabridged
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Time Traveler for measles
The first known use of measles was in the 14th century
See more words from the same century