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.

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

(computing) A program which can covertly transmit itself between computers via networks (especially the Internet) or removable storage such as disks and USB drives, often causing damage to systems and data.

Any extremely contagious filovirus infection of African origin that causes Ebola fever, spread through contact with bodily fluids or secretions of infected persons and by airborne particles, caused by the viruses in genus Ebolavirus.

A concept which is transmitted between people via networks (especially the Internet) generally without the knowledge or consent of the originator, and which may be modified as it is passed on.

a virus, of genus Respirovirus, found in mice but is not pathogenic for humans; it has the ability to generate heterokaryons by fusing cells

(virology, pleonastic) Synonym of HIV (“human immunodeficiency virus”)

Any of many viruses that possess ribonucleic acid as their genetic material and do not replicate using DNA

Any of a group of viruses whose nucleic acid is composed of DNA

Any of several virus strains in genus Norovirus that cause acute gastrointestinal infection. / The disease caused by the virus.