Although the family name of Belcher is a prominent one in English and American history, it is actually Old French in origin. The ancestor of the Belcher family came to England from France, as part of William the Conqueror's army that came to England in the Norman Conquest of 1066 A.D.
(Microbiology) any of several viruses whose genetic specification is encoded in RNA rather than DNA and that are able to reverse the normal flow of genetic information from DNA to RNA by transcribing RNA into DNA: many retroviruses are known to cause cancer in animals.
Retrovirus. Retroviruses are enveloped viruses that belong to the viral family Retroviridae. A retrovirus is an RNA virus that is duplicated in a host cell using the reverse transcriptase enzyme to produce DNA from its RNA genome. On infection, the single-stranded RNA viral genome and the enzyme enters the host cell.he viral genome is released into the host cell, from which a copy of DNA is made by the help of the enzyme reverse transcriptase. The cDNA is integrated into the host chromosome. The virus remains unexpressed until the host's immune system is stimulated.