con ‧ trol ‧ ler /kənˈtrəʊlə $ -ˈtroʊlər/ BrE AmE noun [countable]
[ Word Family: adjective : controlling, ↑ controllable ≠ ↑ uncontrollable , ↑ controlled ≠ ↑ uncontrolled ; noun : ↑ control , ↑ controller ; verb : ↑ control ; adverb : uncontrollably]
1 . someone who is in charge of a particular system, organization, or part of an organization:
air-traffic controllers
2 . ( also comptroller ) formal someone who is in charge of the money received or paid out by a company or government department