virulent

adjective

vir·​u·​lent ˈvir-ə-lənt 

ˈvir-yə-

1

a

: marked by a rapid, severe, and destructive course

a virulent infection

b

: able to overcome bodily defensive mechanisms : markedly pathogenic

virulent bacteria

2

: extremely poisonous or venomous

3

: full of malice : malignant

virulent racists

4

: objectionably harsh or strong

virulent criticism

virulently adverb

Synonyms of virulent

• malicious
• vicious
• cruel
• hateful
• nasty

Examples of virulent in a Sentence

The country seemed to be returning to the virulent nationalism of its past.

the virulent look on her face warned me that she was about to say something unkind

Recent Examples on the Web

This petition must be placed within a tense French context, after several months of virulent criticism aimed at cinema. — Elsa Keslassy, Variety, 4 June 2026

Some of the bacteria that have been detected on the ISS have evolved during their time in space, including salmonella that have become more virulent and acinetobacter pittii that developed resistance to antibiotics. — Scott E. Solomon, STAT, 22 Apr. 2026

Deaths from influenza rose slightly, partly due to an unusually virulent strain circulating last year, although falling vaccination rates may also have contributed, The Wall Street Journal reported. — Tom Chivers, semafor.com, 2 July 2026

Measles is so virulent that at least 95% of a community needs to be vaccinated with two doses of the measles, mumps and rubella (MMR) vaccine to avoid its spread, according to the World Health Organization. — Mary Beth Sheridan, CNN Money, 17 May 2026

Word History

Etymology

Middle English, "discharging watery pus, purulent," borrowed from Latin vīrulentus "full of poison, venomous," from vīrus "venom, poisonous fluid" + -ulentus "having in quantity, full of" — more at virus

First Known Use

14th century, in the meaning defined at sense 1a

Phrases Containing virulent

• hyper-virulent

Rhymes for virulent

• avirulent

Kids Definition

virulent

adjective

vir·​u·​lent ˈvir-(y)ə-lənt 

1

a

: marked by a rapid, severe, and often deadly course

a virulent infection

b

: able to overcome or break down the defenses of the body

a virulent germ

2

: extremely poisonous : noxious

3

: full of hate : spiteful

virulently adverb

Medical Definition

virulent

adjective

vir·​u·​lent -lənt 

1

a

: marked by a rapid, severe, and malignant course

a virulent infection

b

: able to overcome bodily defense mechanisms

a virulent pathogen

2

: extremely poisonous or venomous : noxious