security

strict/tight security =careful security 

lax security =security that is not careful enough  

national/state security =the security of a country against its enemies

 tighten security =make security better  

breach of security =when something dangerous happens, in spite of security measures  

for security reasons  

the security services/forces =the police, army etc 

security camera  

security check   

security measures/arrangements maximum  

security prison/jail