1660s, from Late Latin virulentia, from Latin virulentus "full of poison" (see virulent). Related: Virulency (1610s).
Entries linking to virulence
virulent adj.
c. 1400, in reference to wounds, ulcers, etc., "full of corrupt or poisonous matter," from Latin virulentus "poisonous," from virus "poison" (see virus). Figurative sense of "violent, spiteful" is attested from c. 1600. Related: Virulently.