/ kənˈtrəʊlə(r); NAmE -ˈtroʊ-/ noun
a person who manages or directs sth, especially a large organization or part of an organization
—see also air traffic controller
( technical ) a device that controls or regulates a machine or part of a machine :
a temperature controller
(also comp·trol·ler ) a person who is in charge of the financial accounts of a business company
Middle English (denoting a person who kept a duplicate register of accounts): from Anglo-Norman contrerollour , from contreroller keep a copy of a roll of accounts, from medieval Latin contrarotulare , from contrarotulus copy of a roll, from contra- against + rotulus a roll. Compare with comptroller .