Stands for "Human immunodeficiency virus". contrary to some idiot's beliefs, it was not given to us by the homosexual community. It is believed to originated in Africa from a mutated form of a virus in a diseased monkey. We dont actually know how it came about. It is widely accepted that HIV causes AIDS (acquired immune deficiency syndrome) but becuase we cannot do experiments to prove this (due to morality issues) the African government can claim that there is no evidence supporting this hypothesis and does not have to supply medicine for its citizens.
"Yo my friend just found out that he has HIV, he's gonna try to keep it from becoming AIDS with medicine but the crap thing is that he got it from his girlfriend so they both have it"