Medical Definition of Human immunodeficiency virus. Human immunodeficiency virus: HIV, the cause of AIDS. HIV has also previously been called the human lymphotropic virus type III, the lymphadenopathy-associated virus and the lymphadenopathy virus. No matter what name is applied, it is a retrovirus. (A retrovirus has an RNA genome and a reverse transcriptase enzyme.
Definition of custody for English Language Learners. 1  law : the legal right to take care of a child (such as a child whose parents are divorced) : 2  the state of being kept in a prison or jail. : 3  the act of protecting or taking care of something.
Legal custody is the right and obligation to make long-range decisions about important issues for your child. That means decisions about education, religious training, discipline, medical care, and other significant matters. Legal custody is not related to where a child lives.