operating

adj. relating to or used in surgery (e.g. tools, table, etc.); acting, functioning; managing, using, activating

n. activation (of a device)

v. act, function; manage, use, activate; perform surgery

An operating system (OS) is the software that manages the sharing of the resources of a computer. An operating system processes system data and user input, and responds by allocating and managing tasks and internal system resources as a service to users and programs of the system. At the foundation of all system software, an operating system performs basic tasks such as controlling and allocating memory, prioritizing system requests, controlling input and output devices, facilitating networking and managing file systems. Most operating systems come with an application that provides a user interface for managing the operating system, such as a command line interpreter or graphical user interface. The operating system forms a platform for other system software and for application software. Linux and Mac OS (or any other BSD-derivative) are popular UNIX-like operating systems.
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Adjective
1. involved in a kind of operation; "the operating conditions of the oxidation pond"
(participle) function, work, operate, go, run
2. being in effect or operation; "de facto apartheid is still operational even in the `new' African nations"- Leslie Marmon Silko; "bus service is in operation during the emergency"; "the company had several operating divisions"
(synonym) operational, in operation(p), operating(a)
(similar) operative

Verb
1. direct or control; projects, businesses, etc.; "She is running a relief operation in the Sudan"
(synonym) run
(hypernym) direct
(hyponym) financier
(derivation) operation
2. perform as expected when applied; "The washing machine won't go unless it's plugged in"; "Does this old car still run well?"; "This old radio doesn't work anymore"
(synonym) function, work, go, run
(hyponym) double
(verb-group) run
(derivation) operation, functioning, performance
3. handle and cause to function; "do not operate machinery after imbibing alcohol"; "control the lever"
(synonym) control
(hypernym) manipulate
(hyponym) synchronize, synchronise
(verb-group) master, control
(derivation) operation
4. perform a movement in military or naval tactics in order to secure an advantage in attack or defense
(synonym) manoeuver, maneuver, manoeuvre
(hypernym) move, go
(hyponym) jockey
(derivation) operation, military operation
5. happen; "What is going on in the minds of the people?"
(hypernym) happen, hap, go on, pass off, occur, pass, fall out, come about, take place
(derivation) process, cognitive process, mental process, operation, cognitive operation
6. keep engaged; "engaged the gears"
(synonym) engage, mesh, lock
(hypernym) move, displace
(hyponym) throw, flip, switch
(derivation) operation
7. perform surgery on; "The doctors operated ont he patient but failed to save his life"
(synonym) operate on
(hypernym) treat, care for
(hyponym) sterilize, sterilise, desex, unsex, desexualize, desexualise, fix
(derivation) operation, surgery, surgical operation, surgical procedure, surgical process
(classification) medicine, practice of medicine

n. operating, activation (of a device)

(p. pr. & vb. n.)
of Operate