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: A virus that is composed not of DNA but of RNA. Retroviruses have an enzyme, called reverse transcriptase, that gives them the unique property of transcribing their RNA into DNA after entering a cell.The retroviral DNA can then integrate into the chromosomal DNA of the host cell, to be expressed there. HIV is a retrovirus.etroviruses have an enzyme, called reverse transcriptase, that gives them the unique property of transcribing their RNA into DNA after entering a cell. The retroviral DNA can then integrate into the chromosomal DNA of the host cell, to be expressed there. HIV is a retrovirus.