# virulent

> English word · Adjective · IPA /ˈvɪɹ(j)ʊl(ə)nt/ · frequency rank #33,904

## Definitions
1. Of animals, plants, or substances: extremely venomous or poisonous.
2. Extremely hostile or malicious; intensely acrimonious.
3. Of a disease or disease-causing agent: malignant, able to cause damage to the host.
4. Of a pathogen: replicating within its host cell, then immediately causing it to undergo lysis.

## Etymology
PIE word
 *wisós
From Middle English virulent (“leaking or seeping pus, purulent; (of putrefaction) extremely severe (sense uncertain)”) [and other forms], borrowed from Latin vīrulentus (“poisonous”), from vīrus (“poison; venom; slime, slimy liquid; stinking smell; nasty taste”) (ultimately from Proto-Indo-European *wisós (“poison; slime; fluidity”)) + -ulentus (suffix meaning ‘abounding in, full of’, forming adjectives).
Sense 4 (“of a pathogen: replicating within its host cell, then immediately causing it to undergo lysis”) is derived from French virulent, which was first used in this sense by the French biologist François Jacob (1920–2013) and his co-authors in a 1953 article.

## Easily confused with
- **violent** (https://plainspell.com/en/vs/violent-vs-virulent)
- **virulence** (https://plainspell.com/en/vs/virulence-vs-virulent)

## Common misspellings (12)
`ivrulent`, `virluent`, `virrulent`, `viruelnt`, `virulennt`, `virulentt`, `viruletn`, `virullent`, `virulnet`, `viurlent`, `vriulent`, `vvirulent`

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/en/word/virulent