operation vs work

operation and work both are nouns.

Word	Noun	Adjective	Verb	Adverb
operation	Yes	No	No	No
work	Yes	No	Yes	No

As nouns, work is a hypernym of operation; that is, work is a word with a broader meaning than operation:

operation: a process or series of acts especially of a practical or mechanical nature involved in a particular form of work
work: activity directed toward making or doing something

operation (noun)	work (noun)
a medical procedure involving an incision with instruments; performed to repair damage or arrest disease in a living body	activity directed toward making or doing something
(mathematics) calculation by mathematical methods	the occupation for which you are paid
activity by a military or naval force (as a maneuver or campaign)	a product produced or accomplished through the effort or activity or agency of a person or thing
a planned activity involving many people performing various actions	a place where work is done
a process or series of acts especially of a practical or mechanical nature involved in a particular form of work	the total output of a writer or artist (or a substantial part of it)
a business especially one run on a large scale	applying the mind to learning and understanding a subject (especially by reading)
the activity of operating something (a machine or business etc.)	(physics) a manifestation of energy; the transfer of energy from one physical system to another expressed as the product of a force and the distance through which it moves a body in the direction of that force
(psychology) the performance of some composite cognitive activity; an operation that affects mental contents
(computer science) data processing in which the result is completely specified by a rule (especially the processing that results from a single instruction)
process or manner of functioning or operating
the state of being in effect or being operative

operation (verb)	work (verb)
	give a workout to
	arrive at a certain condition through repeated motion
	go sour or spoil
	cause to undergo fermentation
	find the solution to (a problem or question) or understand the meaning of
	use or manipulate to one's advantage
	to mix into a homogeneous mass
	perform as expected when applied
	move into or onto
	shape, form, or improve a material
	cause to happen or to occur as a consequence
	prepare for crops
	make something, usually for a specific function
	gratify and charm, usually in order to influence
	proceed along a path
	move in an agitated manner
	provoke or excite
	be employed
	cause to work
	exert oneself by doing mental or physical work for a purpose or out of necessity; work
	have an effect or outcome; often the one desired or expected
	operate in a certain place, area, or specialty
	proceed towards a goal or along a path or through an activity
	have and exert influence or effect
	operate in or through
	cause to operate or function
	behave in a certain way when handled