You can refer to a building as a safe house when it is used as a place where someone can stay and be protected. Safe houses are often used by spies, criminals, or the police. a farm which operates as a safe house for criminals on the run. A house or apartment used as a hiding place or secure refuge by the members of an organization, such as a secret service agency or an underground terrorist group. a house where someone can hide and be protected. Safe houses are used especially by criminals hiding from the police, or by people who are being protected by the police