Physical custody – this legal phrase has several different meanings, depending of the usage:
1) In terms of Family Law, physical custody details a child custody decision which grants a certain person (who is not the parent of the child) the legal right to organize and administer the day to day residential care, feed and parental supervision of a child. This is usually combined with legal custody, which sets which person will make decisions on behalf and in the name of the child – then he is called “personal representative”.
2) When related to the parent of the child, it refers to their rights to have their child living with them, and at the same time refers to the obligations which the parent has to grow, feed, educate and share good behavior to their children. A synonym for this concrete meaning is “residential custody”. Eventual lack of parental care, safety and emotional needs, or eventual abandonment represents physical negligence.
3) In the Criminal Law this phrase may refer to the arrest of person, where their freedom is limited and controlled by the police within a physically secure facility.
See also: http://www.attorneys.com/divorce/primary-physical-custody/