A large cell where prisoners (people awaiting trial or sentence or refugees or illegal immigrants) are confined together temporarily WordNet 3.0 & Open English WordNet

An immigration detention facility; a facility in which people who have attempted to enter Australia without prior authorisation are detained, pending a decision on whether they are to be accepted as refugees or returned to their country of origin. Wiktionary

A cell in a police station or courthouse in which a prisoner is held temporarily, pending charge, trial or sentencing. Wiktionary