Search Warrant (noun) – A judicial order that peace officers may enter a specific location and search for specified evidence of a crime. A search warrant is an official instrument that authorizes police officers to enter a specific location or otherwise to invade a private activity, and thus to search for specified forms of evidence related to specific behavior in violation of the criminal law.

A search warrant must be dated and signed by the judge or magistrate who enters it, and it is subject to the limits of the Fourth Amendment, so that a search warrant must be based on probable cause, which is to say that the magistrate or judge who issues the warrant must have done so only after finding there is probable cause to believe that the premises to be searched will contain evidence of a crime.