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.

• enPR: vīʹrəs, IPA^(key): /ˈvaɪ.ɹəs/

• Audio (US):

  (file)

• Rhymes: -aɪɹəs

virus (countable and uncountable, plural viruses or (rare) virusses or (rare) vira or (proscribed) viri or (proscribed) virii or (rare, nonstandard) virus)

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).

   Synonyms: see Thesaurus:virus

   • 2001, Leslie Iversen, Drugs: A Very Short Introduction, Oxford, page 64:

     Viruses are the smallest and most simplified forms of life.

   • 2013 May-June, Katie L. Burke, “In the News”, in American Scientist, volume 101, number 3, page 193:

     Bats host many high-profile viruses that can infect humans, including severe acute respiratory syndrome and Ebola.

   1. A species thereof.

      Meronym: virion (individual particle)

      Some viruses, such as norovirus, cause sporadic outbreaks of gastroenteritis.

   2. (occasionally proscribed) An individual particle thereof: synonym of virion.

      Under electron microscopy, a few viruses were seen floating near the cells.

3. (uncountable) A quantity of such infectious agents, considered en masse.

   Not much virus was detectable on a nucleic acid test; the viral load was very low.

   • 2006, Norman E. Borlaug, Anthony Cunningham, Jane I. Guyer, Hans R. Herren, Calestous Juma, Akinlawon Mabogunje, Barbara Underwood, Montague Yudelman, chapter 1, in Lost Crops of Africa: Volume 2: Vegetables (U.S. National Research Council Consensus Study Report)‎^[1] (non-fiction), Washington, D.C.: National Academies Press, →DOI, →ISBN, →LCCN, →OCLC, →OL, archived from the original on 2 September 2021, page xviii:

     Unless professionally inspected, they [plants] may also carry along unseen pests and diseases (particularly small insects and microbes such as virus or bacteria) whose populations might explode catastrophically in new locations.

4. (informal, metonymic) A disease caused by such an infectious agent; a viral illness.

   He's got a virus and had to stay home from school.

5. (archaic) Venom, as produced by a poisonous animal etc.
   • 1890, Aluísio Azevedo, The Slum:

     Brazil, that inferno where every budding flower and every buzzing bluebottle fly bears a lascivious virus.

6. (computing) 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.
   • 2004 November 15, Michael Chapman; Matthew Chapman, “Strong Bad Email #118: virus”, in Homestar Runner‎^[2], spoken by Strong Bad (Matthew Chapman):

     Wait a minute! Is this one of those virus emails?!

7. (computing, proscribed) Any type of malware.
8. (figurative) Any malicious or dangerous entity that spreads from one place or person to another.
   • 2011, Pat Mesiti, The $1 Million Reason to Change Your Mind:

     I am tired of the mind viruses that are crippling people living in the western world — especially in my own nation. Sadly, Australia is becoming known as a nation of whingers.

• (computing): malware

virus (third-person singular simple present viruses, present participle virusing, simple past and past participle virused)

1. (nonstandard, rare) To send or infect an electronic device with a computer virus.

   I'm just going to virus anyone who tries cheating on this game.

• prion

• Plural form of words ending in -us § Virus on Wikipedia.Wikipedia
• Virus on Wikipedia.Wikipedia
• Computer virus on Wikipedia.Wikipedia
• Virus on Wikispecies.Wikispecies

From Latin vīrus.

• IPA^(key): /ˈbiɾus/ [ˈbi.ɾus]
• Rhymes: -iɾus
• Syllabification: vi‧rus

virus m (plural virus)

1. virus

Ultimately from Latin vīrus.

virus (definite accusative virusu, plural viruslar)

1. (medicine) virus
2. (computing) computer virus

• “virus” in Obastan.com.

Borrowed from Latin vīrus.

• IPA^(key): (Central) [ˈbi.ɾus]
• IPA^(key): (Balearic, Valencia) [ˈvi.ɾus]

• Audio (Catalonia):

  (file)

virus m (invariable)

1. virus

• viral
• víric
• virologia

• “virus”, in Gran Diccionari de la Llengua Catalana, Grup Enciclopèdia Catalana, 2026

Borrowed from English virus, from Latin vīrus, from Proto-Italic *weizos, ultimately from Proto-Indo-European *wisós (“poison”).

• (Revived Middle Cornish) IPA^(key): [ˈviːrʏs]
• (Revived Late Cornish) IPA^(key): [ˈviːrɪz]

virus m (plural virusys)

1. virus

• “virus” in Cornish Dictionary / Gerlyver Kernewek, Akademi Kernewek.
• Akademi Kernewek Gerlyver Kernewek (FSS) Cornish Dictionary (SWF) (in Cornish), 2018, published 2018, page 190

Borrowed from Russian вирус (virus).

virus

1. (virology) virus

• “virus”, in Luğatçıq (in Russian)

• vir

Borrowed from Latin vīrus.

• IPA^(key): [ˈvɪrus]

virus m inan

1. (virology) virus (a submicroscopic, non-cellular structure)
2. (computing) virus (a type of computer malware)

• “virus”, in Příruční slovník jazyka českého (in Czech), 1935–1957
• “virus”, in Slovník spisovného jazyka českého (in Czech), 1960–1971, 1989
• “virus”, in Internetová jazyková příručka (in Czech), 2008–2026

From Latin vīrus.

virus c or n (singular definite virussen or virusset, plural indefinite virus or virusser or vira, plural definite virussene or virusserne or viraene)

1. virus

From Latin vīrus. Coined in the virological sense by Martinus Beijerinck; the word had been previously used for pathogens, although not for viruses in the modern sense. The computing sense derives from English virus.

• IPA^(key): /ˈviː.rʏs/

• Audio:

  (file)

• Hyphenation: vi‧rus

virus n (plural virussen, diminutive virusje n)

1. (microbiology) virus
2. (computer science) virus (computer virus)

Like most Latin borrowings, this word kept its original Latin gender (neuter); it is one of the few Dutch words ending in -us which is not masculine; cf. also corpus and opus. Marginally, use as a masculine noun is sometimes erroneously encountered, indeed based on the ending.

• viroloog

From Latin vīrus.

• IPA^(key): /ˈʋirus/, [ˈʋirus̠]
• IPA^(key): /ˈʋiːrus/, [ˈʋiːrus̠] (proscribed)
• Rhymes: -irus
• Syllabification^(key): vi‧rus
• Hyphenation^(key): vi‧rus

virus

1. (medicine, countable, uncountable) virus

   Viruksen voi nähdä pyyhkäisyelektronimikroskoopilla. ― You can see a virus with a scanning electron microscope.

   Onko marjoissa norovirusta? ― Is there norovirus in berries?

2. (computer security, countable) virus, computer virus

   Huomio! Tietokoneeseesi on tunkeutunut virus. ― Attention! A virus has invaded you computer.

• “virus”, in Kielitoimiston sanakirja [Dictionary of Contemporary Finnish]‎^[3] (in Finnish) (online dictionary, continuously updated), Kotimaisten kielten keskuksen verkkojulkaisuja 35, Helsinki: Kotimaisten kielten tutkimuskeskus (Institute for the Languages of Finland), 2004–, retrieved 4 July 2023

• virsu

Borrowed from Latin vīrus.

• IPA^(key): /vi.ʁys/

• Audio:

  (file)

• Audio (France (Vosges)):

  (file)

• Audio (France):

  (file)

• Audio (France (Vosges)):

  (file)

virus m (invariable)

1. virus

• “virus”, in Trésor de la langue française informatisé [Digitized Treasury of the French Language], 2012

Learned borrowing from Latin vīrus (“poison, slime, venom”).

virus m (invariable)

1. virus (pathogen)
2. computer virus

Borrowed from Dutch virus, from Latin vīrus (“poison, slime, venom”), via rhotacism from Proto-Italic *weizos, from Proto-Indo-European *wisós (“fluidity, slime, poison”). Doublet of bisa. The computing sense is a semantic loan from English virus.

• (Standard Indonesian) IPA^(key): /ˈvirus/ [ˈfi.rʊs]
• Rhymes: -irus
• Syllabification: vi‧rus

virus (plural virus-virus)

1. virus; a type of submicroscopic infectious organism
2. virus (in quantity)

   Synonym: (uncommon) virus utuh

3. (metonymic) virus, viral illness
4. (computing) virus; a type of spreading malware
5. (computing, colloquial) virus; any type of malware

   Synonym: perangkat pembahaya

6. (figurative) any malicious or dangerous entity that spreads from one place or person to another.

• “virus”, in Kamus Besar Bahasa Indonesia [Great Dictionary of the Indonesian Language] (in Indonesian), Jakarta: Agency for Language Development and Cultivation – Ministry of Education, Culture, Research, and Technology of the Republic of Indonesia, 2016

virus (plural viruses)

1. virus

• virusal

Borrowed from Latin vīrus.

• IPA^(key): /ˈvi.rus/
• Rhymes: -irus
• Hyphenation: vì‧rus

virus m (invariable)

1. (virology) virus

• virus in Treccani.it – Vocabolario Treccani on line, Istituto dell'Enciclopedia Italiana

• IPA^(key): /ˈvirus/

virus m

1. virus
   • 2018 February 7, Dora Niyego, “El Antisemitizmo De Oy”, in Şalom‎^[4]:

     El antisemitizmo es un prejudizio, komo un virus.

     Antisemitism is a prejudice, like a virus.

Via rhotacism from Proto-Italic *weizos, from Proto-Indo-European *wisós (“fluidity, slime, poison”). Cognates include Sanskrit विष (viṣá), Ancient Greek ἰός (iós, “poison”), Tocharian B wase, and Middle Irish fí. The neuter gender, despite its nominative singular ending -us being typical of the masculine second declension, is possibly a relic of this term's inheritance from a neuter s-stem.^[1]

• (Classical Latin) IPA^(key): [ˈwiː.rʊs]
• (modern Italianate Ecclesiastical) IPA^(key): [ˈviː.rus]

vīrus n sg (genitive vīrī); second declension

1. venom (a poisonous substance secreted by animals or plants)

   Synonym: venēnum

2. a plant- or animal-sourced substance with medicinal or magical properties
3. a liquid element that makes something taste or smell bitter or acrid
   1. (transferred sense) bitterness, acrimony (of speech, manner or disposition)
4. (New Latin) a virus (infectious organism)

• In Classical Latin, forms other than the nominative/accusative singular are rarely used.^[1][2] Some Late Latin grammarians such as Pseudo-Probus and Servius treat vīrus as a defective indeclinable noun with only three cases (nominative/accusative/vocative), implying that the genitive, dative, and ablative singular inflected forms had become obsolete in their time.^[3][4] Martianus Capella and Priscian describe it as indeclinable without specifying in which cases it is used.^[5][6] An alternative genitive singular form vīrus or vīrūs is attested in the 4th-century author Ammianus Marcellinus.^[7] Some New Latin authors use the full inflection paradigm with plural forms shown below.

Second-declension noun (neuter, nominative/accusative/vocative in -us), singular only.

In New Latin, sometimes declined as a second declension noun (neuter, nominative/accusative/vocative in -us), with plural.^[8]

• "virus", in Charlton T. Lewis and Charles Short (1879), A Latin Dictionary, Oxford: Clarendon Press
• "virus". in Charlton T. Lewis (1891), An Elementary Latin Dictionary, New York: Harper & Brothers
• "virus", in Charles du Fresne du Cange, Glossarium Mediæ et Infimæ Latinitatis (augmented edition with additions by D. P. Carpenterius, Adelungius and others, edited by Léopold Favre, 1883–1887)
• "virus", in William Smith, editor (1854, 1857), A Dictionary of Greek and Roman Geography, volume 1 & 2, London: Walton and Maberly
• “uīrus” on page 2286 of the Oxford Latin Dictionary (2nd ed., 2012)

• rivus

(This etymology is missing or incomplete. Please add to it, or discuss it at the Etymology scriptorium.)

• IPA^(key): /ˈviː²ʀəs/

virus n (plural virusse, diminutive viruske)

1. (virology) virus (infectious organism)
2. (computing) virus (infectious software)

• “virus”, in D'n Dictionair‎^[5] (overall work in English, Dutch, and Limburgish), Limburgish Academy, 2007-present

• IPA^(key): /ˈvʲɪrʊs/

vi̇̀rus

1. active adverbial past half-participle of vi̇̀rti

From English virus, from Latin vīrus, from rhotacism from Proto-Italic *weizos.

• IPA^(key): /virus/, /vajrəs/

virus (plural virus-virus)

1. virus:
   1. (biology, virology) A submicroscopic, non-cellular structure consisting of a core of DNA or RNA surrounded by a protein coat, that requires a living host cell to replicate, and often causes disease in the host organism; such agents are often classed as nonliving infectious particles and less often as microorganisms.

(This etymology is missing or incomplete. Please add to it, or discuss it at the Etymology scriptorium.)

virus

1. virus

Odd, no gradation
Nominative	virus
Genitive	virusa
	Singular	Plural
Nominative	virus	virusat
Accusative	virusa	virusiid
Genitive	virusa	virusiid
Illative	virusii	virusiidda
Locative	virusis	virusiin
Comitative	virusiin	virusiiguin
Essive	virusin
Possessive forms Singular Dual Plural 1st person virusan viruseamẹ viruseamẹt 2nd person virusat viruseattẹ viruseattẹt 3rd person virusis viruseaskkạ viruseasẹt

From Latin vīrus.

virus n (definite singular viruset, indefinite plural virus, definite plural virusa or virusene)

1. (biology, virology) virus
2. (computing) virus (computer virus) (see datavirus)

• “virus” in The Bokmål Dictionary.

From Latin virus.

virus n (definite singular viruset, indefinite plural virus, definite plural virusa)

1. (biology, virology) virus
2. (computing) virus (computer virus) (see datavirus)

• “virus” in The Nynorsk Dictionary.

Borrowed from French virus, Latin vīrus.

• IPA^(key): /ˈvirus/
• Rhymes: -irus
• Hyphenation: vi‧rus

virus n (plural virusuri)

1. (virology) virus (a submicroscopic, non-cellular structure)

virus m (plural viruși)

1. (computing) virus (a type of computer malware)

vírus m inan (Cyrillic spelling ви́рус)

1. (medicine) virus (DNA/RNA causing disease)
2. (computing) computer virus

Borrowed from Latin vīrus.

• IPA^(key): /ˈbiɾus/ [ˈbi.ɾus]

• Audio (Colombia):

  (file)

• Rhymes: -iɾus
• Syllabification: vi‧rus

virus m (plural virus)

1. virus
   • 2023 August 22, Jamie Gumbrecht, “La FDA aprueba la primera vacuna para proteger a los recién nacidos del virus respiratorio sincitial”, in CNN en Español‎^[6]:

     La Administración de Alimentos y Medicamentos de Estados Unidos (FDA, por sus siglas en inglés) aprobó este lunes la primera vacuna que protege a los recién nacidos del virus respiratorio sincitial, conocido como RSV (por sus siglas en inglés).

     (please add an English translation of this quotation)

2. computer virus

• “virus”, in Diccionario de la lengua española [Dictionary of the Spanish Language] (in Spanish), online version 23.8.1, Royal Spanish Academy [Spanish: Real Academia Española], 15 December 2025

From Latin vīrus.

• IPA^(key): /ˈviːrɵs/
• Rhymes: -¹iːrɵs

virus n

1. (biology, virology) virus
2. (computing) computer virus

   Synonyms: datavirus, datorvirus

• viral

• bacill
• bakterie

• “virus”, in Svensk ordbok [Dictionary of Swedish] (in Swedish)
• “virus”, in Svenska Akademiens ordlista [Wordlist of the Swedish Academy] (in Swedish)
• “virus”, in Svenska Akademiens ordbok [Dictionary of the Swedish Academy] (in Swedish)
• Svensk MeSH

• bayrus, vayrus
• birus

Unadapted borrowing from English virus, from Latin vīrus. Doublet of bisa and birus. Used due to Tagalog-English code-switching (Taglish).

• (Standard Tagalog) IPA^(key): /ˈvajɾus/ [ˈvaɪ̯.ɾʊs]
  • IPA^(key): (with nativization) /ˈbajɾus/ [ˈbaɪ̯.ɾʊs]
  • Rhymes: -ajɾus
• (nonstandard) IPA^(key): /ˈviɾus/ [ˈviː.ɾʊs]
  • IPA^(key): (with nativization) /ˈbiɾus/ [ˈbiː.ɾʊs]
  • Rhymes: -iɾus
• Syllabification: vi‧rus

virus (Baybayin spelling ᜊᜌ᜔ᜇᜓᜐ᜔ or ᜊᜒᜇᜓᜐ᜔)

1. (biology, virology) virus

   Synonyms: birus, (neologism) haykap

2. (computing) computer virus

• “virus”, in Pambansang Diksiyonaryo | Diksiyonaryo.ph, 2018