The definition of measles is a highly contagious and dangerous disease which is caused by a virus, paramyxovirus.
An example of measles is an itchy red rash which starts at the ears.
See measles in Webster's New World College Dictionary
Origin: ME maseles, pl. of masel, measle, spot (? infl. by mesel, leper < OFr < L misellus, wretch < miser, wretched), akin to OHG māsa, a spot, Ger masern, measles
See measles in American Heritage Dictionary 4
noun (used with a sing. or pl. verb)
Origin: Middle English maseles, mesels
Origin: , pl. of masel, measles-spot
Origin: , of Middle Low German origin.
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