vir·u·lent (vîryə-lənt, vîrə-)
a. Characterized by, causing, or promoting the rapid onset of severe illness. Used of a disease or toxin.
b. Capable of causing disease by aggressively interfering with the immune system of the host. Used of a pathogen.
2. Extremely hostile or malicious: virulent criticism; a virulent bigot.
[Middle English, from Latin vīrulentus, from vīrus, poison.]
viru·lence, viru·len·cy n.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2019 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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