said of a person's expression or behaviour: deliberately calm
His tone was quiet and controlled — Edith Wharton
said of an experiment or trial: in which testing is simultaneously carried out on a control2 (a subject not given the treatment under trial), or in which possible extraneous factors are controlled for, or taken into account
said of a drug: that has legal restrictions on its use and possession
said of an aircraft's flight: directed from the ground or from another aircraft