noun · verb · 13 senses · updated from the 2026-07-25 local source snapshot
Definitions and examples are grouped by meaning. Pronunciation, history, word forms, translations, descendants, synonyms, antonyms, derived terms, and related words appear whenever the source provides them.
Sound
Pronunciation
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vīʹrəs
/ˈvaɪ.ɹəs/
US:Recorded audio is listed in the source snapshot.
rhymes with -aɪɹəs
CMU ARPABET:V AY1 R AH0 S
Digits mark lexical stress: 1 primary, 2 secondary, 0 unstressed.
1
noun
Meaning 1
A submicroscopic, non-cellular structure that consists of a core of DNA or RNA surrounded by a protein coat, that requires a living host cell to replicate, and that sometimes causes disease in the host organism (such agents are often classed as nonliving infectious particles and less often as microorganisms).
Definition source: English Wiktionary via Wiktextract
Usage: countable, uncountable
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
2
noun
Meaning 2
A submicroscopic, non-cellular structure that consists of a core of DNA or RNA surrounded by a protein coat, that requires a living host cell to replicate, and that sometimes causes disease in the host organism (such agents are often classed as nonliving infectious particles and less often as microorganisms).
A species thereof.
Definition source: English Wiktionary via Wiktextract
Usage: countable, uncountable
Examples
Meronym: virion (individual particle)
Some viruses, such as norovirus, cause sporadic outbreaks of gastroenteritis.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
3
noun
Meaning 3
A submicroscopic, non-cellular structure that consists of a core of DNA or RNA surrounded by a protein coat, that requires a living host cell to replicate, and that sometimes causes disease in the host organism (such agents are often classed as nonliving infectious particles and less often as microorganisms).
An individual particle thereof: synonym of virion.
Definition source: English Wiktionary via Wiktextract
Usage: countable, uncountable
Qualifier: occasionally proscribed
Examples
Under electron microscopy, a few viruses were seen floating near the cells.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
4
noun
Meaning 4
A quantity of such infectious agents, considered en masse.
Definition source: English Wiktionary via Wiktextract
Usage: uncountable
Examples
Not much virus was detectable on a nucleic acid test; the viral load was very low.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
5
noun
Meaning 5
A disease caused by such an infectious agent; a viral illness.
Definition source: English Wiktionary via Wiktextract
He's got a virus and had to stay home from school.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
6
noun
Meaning 6
Venom, as produced by a poisonous animal etc.
Definition source: English Wiktionary via Wiktextract
Usage: archaic, countable, uncountable
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
7
noun
Meaning 7
A type of malware which can covertly transmit itself between computers via networks (especially the Internet) or removable storage such as disks, often causing damage to systems and data; also computer virus.
Definition source: English Wiktionary via Wiktextract
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
9
noun
Meaning 9
Any malicious or dangerous entity that spreads from one place or person to another.
Definition source: English Wiktionary via Wiktextract
Usage: countable, figuratively, uncountable
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
10
verb
Meaning 10
To send or infect an electronic device with a computer virus.
Definition source: English Wiktionary via Wiktextract
Usage: nonstandard, rare
Examples
I'm just going to virus anyone who tries cheating on this game.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
11
noun
Meaning 11
(virology) ultramicroscopic infectious agent that replicates itself only within cells of living hosts; many are pathogenic; a piece of nucleic acid (DNA or RNA) wrapped in a thin coat of protein
Definition source: Princeton WordNet 3.0
No example sentence was provided for this meaning.
a software program capable of reproducing itself and usually capable of causing great harm to files or other programs on the same computer
Definition source: Princeton WordNet 3.0
Examples
a true virus cannot spread to another computer without human assistance
Meaning relationships
Synonyms: computer virus
Antonyms: none provided
Broader terms: malevolent program
13
noun
Meaning 13
a harmful or corrupting agency
Definition source: Princeton WordNet 3.0
Examples
bigotry is a virus that must not be allowed to spread
the virus of jealousy is latent in everyone
Meaning relationships
Synonyms: none provided
Antonyms: none provided
Broader terms: representation, delegacy, agency
History
Etymology
Etymology tree Proto-Indo-European *weys- Proto-Indo-European *wisós Proto-Italic *weizos Latin vīrusbor. Middle English virus English virus From Middle English virus, from Latin vīrus (“poison, slime, venom”), via rhotacism from Proto-Italic *weizos, from Proto-Indo-European *wisós (“fluidity, slime, poison”). First use in the computer context by David Gerrold in his 1972 book When HARLIE Was One.
Across languages
Translations
247 source translations are retained for this English entry.
