Barbed-wire entanglement is a term used to describe a barrier made of sharp metal spikes that are twisted together to form an obstacle. There are several synonyms for this term, such as razor wire, concertina wire, and coil wire. Razor wire is made of a single strand of sharp razor blades, which provides a high level of security. Concertina wire is a type of barbed wire that is formed into coils, making it easier to install and maintain. Coil wire is a type of barbed wire that is used for agricultural and pastoral purposes to contain animals. These synonyms for barbed-wire entanglement are often used in military, security, and prison contexts to deter intrusion and escape.