operation

noun

1 the slide bars are machined to ensure smooth operation:

functioning, working, running, performance, action, behaviour.

2 those responsible for the operation of the factory:

management, running, direction, control, governing, administration, supervision.

3 legislation to curtail the operation of the closed shop:

effect, force, potency, power, effectiveness.

4 a heart bypass operation:

surgery, surgical operation, surgical intervention, major surgery, minor surgery.

5 a carefully planned military operation:

action, activity, exercise, affair, business, undertaking, step, enterprise, task, job, process, procedure, manoeuvre, campaign.

6 the company's South American mining operation:

business, enterprise, company, firm, organization, concern;

informal outfit, set-up.

□ in operation

only the starboard engine was in operation:

functioning, working, running, up and running, operative, in use, in action, going;

operational, workable, serviceable, functional, usable, in working order/condition, viable;

in force, effective, in effect, valid.

operation Oxford Dictionary of English