pl.n. (used with a sing. or pl. verb)
An acute, inflammatory, contagious disease caused by a paramyxovirus and characterized by swelling of the salivary glands, especially the parotids, and sometimes of the pancreas, ovaries, or testes. This disease, mainly affecting children, can be prevented by vaccination.
[Perhaps from pl. of dialectal mump, grimace.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2020 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
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