boss [bosses](supervisor) noun [UK: bɒs] [US: ˈbɒs]
supervisor [supervisors](a person with the official task of overseeing the work of a person or group etc.) noun [UK: ˈsuː.pə.vaɪ.zə(r)] [US: ˈsuː.pər.ˌvaɪ.zər]
warden [wardens](an official charged with supervisory duties) noun [UK: ˈwɔːd.n̩] [US: ˈwɔːr.dn̩]