# virus

> English word · Noun · IPA /ˈvaɪ.ɹəs/ · frequency rank #3,537

## Definitions
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).
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).
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).
4. A quantity of such infectious agents, considered en masse.
5. A disease caused by such an infectious agent; a viral illness.
6. Venom, as produced by a poisonous animal etc.
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.
8. Any type of malware.
9. Any malicious or dangerous entity that spreads from one place or person to another.

## Etymology
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.

## Easily confused with
- **vis** (https://plainspell.com/en/vs/virus-vs-vis)
- **viruses** (https://plainspell.com/en/vs/virus-vs-viruses)
- **vers** (https://plainspell.com/en/vs/vers-vs-virus)
- **views** (https://plainspell.com/en/vs/views-vs-virus)
- **viral** (https://plainspell.com/en/vs/viral-vs-virus)
- **Venus** (https://plainspell.com/en/vs/venus-vs-virus)
- **vines** (https://plainspell.com/en/vs/vines-vs-virus)
- **vibes** (https://plainspell.com/en/vs/vibes-vs-virus)
- **Virgo** (https://plainspell.com/en/vs/virgo-vs-virus)
- **Varun** (https://plainspell.com/en/vs/varun-vs-virus)
- **Virat** (https://plainspell.com/en/vs/virat-vs-virus)
- **Vikas** (https://plainspell.com/en/vs/vikas-vs-virus)
- **versus** (https://plainspell.com/en/vs/versus-vs-virus)
- **virtue** (https://plainspell.com/en/vs/virtue-vs-virus)
- **virtues** (https://plainspell.com/en/vs/virtues-vs-virus)

## Common misspellings (7)
`ivrus`, `virrus`, `virsu`, `viruss`, `viurs`, `vrius`, `vvirus`

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