There are more than hundred english-english dictionaries in the world. According to merriam-websters website: Webster's Third New International Dictionary, Unabridged, together with its 1993 Addenda Section, includes some 470,000 entries.
Most commonly, HIV infection is spread by having sex with an infected partner. The virus can enter the body through the lining of the vagina, vulva, penis, rectum, or mouth during sex. Although vaginal and anal intercourse are the primary risk factors, oral sex transmission is also possible.
The original name for HIV, the virus that causes AIDS, was HTLV-III. The HTLV-1 genome is diploid, composed of two copies of a single-stranded RNA virus whose genome is copied into a double-stranded DNA form that integrates into the host cell genome, at which point the virus is referred to as a provirus.