how did it get its name?
From the Latin word ”Virulent” that refers to poison.
Virus
The word is from the Latin neuter referring to poison and other noxious liquids, from the same Indo-European base as Sanskrit , Avestan , and ancient Greek (all meaning "poison"), first attested in English in 1398 in John Trevisa's translation of Bartholomeus Anglicus's "De Proprietatibus Rerum". "Virulent", from Latin "virulentus" (poisonous), dates to c. 1400.
when does the genetic material of a host and a virus combine Only when the host is infected by the virus. can you please define the latter term? It is a submicroscopic infectious agent that replicates only inside the living cells of an organism.
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Virus [SEP] Etymology
The word is from the Latin neuter referring to poison and other noxious liquids, from the same Indo-European base as Sanskrit , Avestan , and ancient Greek (all meaning "poison"), first attested in English in 1398 in John Trevisa's translation of Bartholomeus Anglicus's "De Proprietatibus Rerum". "Virulent", from Latin "virulentus" (poisonous), dates to c. 1400. A meaning of "agent that causes infectious disease" is first recorded in 1728, long before the discovery of viruses by Dmitri Ivanovsky in 1892. The English plural is "viruses" (sometimes also "vira"), whereas the Latin word is a mass noun, which has no classically attested plural ("vīra" is used in Neo-Latin).