The person in charge of a prison. (Cambridge Dictionary)
A person who is in charge of (the people) in a particular building. (Cambridge Dictionary)
The head of a college. (Cambridge Dictionary)
A person responsible for the supervision of a particular place or activity or for enforcing the regulations associated with it. (Oxford Dictionaries)
The head of certain schools, colleges, or other institutions. (Oxford Dictionaries)
A warden is a person who is responsible for a particular place or thing, and for making sure that the laws or regulations that relate to it are obeyed. (Collins Dictionary)
7 key duties of a fire warden.
Prison Warden: Job Description, Duties and Requirements.