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.
HIV/AIDS. HIV, or human immunodeficiency virus, is the virus that causes AIDS (Acquired Immunodeficiency Syndrome). HIV attacks the immune system by destroying CD4 positive (CD4+) T cells, a type of white blood cell that is vital to fighting off infection. The destruction of these cells leaves people living with HIV vulnerable to other infections, diseases and other complications.