high-securityBrE /ˌhaɪ sɪˈkjʊərəti/ 🔊NAmE /ˌhaɪ sɪˈkjʊrəti/ 🔊 adjective [only before noun] (of buildings and places 建筑或地方) very carefully locked and guarded 戒备森严的；警戒严密的◆a high-security prison警备森严的监狱(of prisoners 囚犯) kept in a prison that is very carefully locked and guarded 关押在警备森严的监狱里的