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.
Physical custody refers to where the child lives, and how much time the child spends with each parent. Depending on the laws of the state, the court may award sole custody, joint custody, or primary physical custody. With sole custody, the child only lives with one parent, while the other parent may have scheduled visitation or parenting time.