1 MACHINEa) (T) to use and control a machine or equipment: If affected by drowsiness, do not drive or operate heavy machinery. | instructions for operating the central heatingb) (intransitive always + adv/prep) if a machine operates in a particular way, it works in that way; function 2(+ in/at): a motor operating at high speeds.2 SYSTEM/PROCESS/SERVICEa) (I) if a system, process etc operates, it works in a particular way or for a particular purpose: How well does your company's decision-making system operate in practice? | The new law doesn't operate in our favour.b) (T) if you operate a system, service etc, you make it work: St. Mark's School operates a system of rewards and punishments.3 MEDICAL (I) to cut open someone's body in order to remove or repair a part that is damaged: It's serious. We'll have to operate immediately.(+ on/for): Doctors had to operate on his spine.4 BUSINESS/ORGANIZATION (intransitive always + adv/prep) to work in a particular place or way(+ in/within/from): rival gangs that operate in the south side of the city | a small company operating out of a converted barn5 WORK (I) to do your job or try to achieve things in a particular way: Soldiers cannot operate effectively without good food. | That's just the way she operates.6 operate as to have a particular purpose: The word `onward' can operate as an adjective and an adverb. | Our consciences operate as a check on our behaviour.7 LAWS/PRINCIPLES (I) to have an effect on something: evolutionary principles operating in the physical world
Longman dictionary of contemporary English. 2004.