en ‧ forc ‧ er /ɪnˈfɔːsə $ -ˈfɔːrsər/ BrE AmE noun [countable]
[ Word Family: noun : ↑ enforcement , ↑ enforcer ; adjective : ↑ enforceable , ↑ enforced ; verb : ↑ enforce ]
someone whose job is to make sure people do the things they should:
a law enforcer
an enforcer for a drugs gang