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vir·u·lent

(vîryə-lənt, vîrə-)

adj.

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.]

viru·lence, viru·len·cy n.

viru·lent·ly adv.

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:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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