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.
A retrovirus is a virus that uses RNA as its genetic material. When a retrovirus infects a cell, it makes a DNA copy of its genome that is inserted into the DNA of the host cell.There are a variety of different retroviruses that cause human diseases, including the common cold, some forms of cancer, and AIDS.t uses an enzyme called reverse transcriptase to become part of the host cells' DNA. This allows many copies of the virus to be made in the host cells. The virus that causes AIDS, the human immunodeficiency virus (HIV), is a type of retrovirus.