n. (used with a sing. or pl. verb)
a. An acute, contagious viral disease, usually occurring in childhood and characterized by eruption of red spots on the skin, fever, and catarrhal symptoms. Also called rubeola.
b. Black measles.
c. Any of several other diseases, especially German measles, that cause similar but milder symptoms.
2. A condition of pork or beef caused by the presence of tapeworm larvae.
3. A plant disease, usually caused by fungi, that produces small spots on leaves, stems, or fruit.
[Middle English maseles, mesels, pl. of masel, measles-spot, of Middle Low German origin.]
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