From WordNet (r) 3.0 (2006) [wn]:
operation
n 1: the state of being in effect or being operative; "that rule
is no longer in operation"
2: a business especially one run on a large scale; "a large-
scale farming operation"; "a multinational operation"; "they
paid taxes on every stage of the operation"; "they had to
consolidate their operations"
3: a planned activity involving many people performing various
actions; "they organized a rescue operation"; "the biggest
police operation in French history"; "running a restaurant is
quite an operation"; "consolidate the companies various
operations"
4: (computer science) data processing in which the result is
completely specified by a rule (especially the processing
that results from a single instruction); "it can perform
millions of operations per second"
5: activity by a military or naval force (as a maneuver or
campaign); "it was a joint operation of the navy and air
force" [syn: operation, military operation]
6: a medical procedure involving an incision with instruments;
performed to repair damage or arrest disease in a living
body; "they will schedule the operation as soon as an
operating room is available"; "he died while undergoing
surgery" [syn: operation, surgery, surgical operation,
surgical procedure, surgical process]
7: a process or series of acts especially of a practical or
mechanical nature involved in a particular form of work; "the
operations in building a house"; "certain machine tool
operations" [syn: operation, procedure]
8: process or manner of functioning or operating; "the power of
its engine determines its operation"; "the plane's operation
in high winds"; "they compared the cooking performance of
each oven"; "the jet's performance conformed to high
standards" [syn: operation, functioning, performance]
9: (psychology) the performance of some composite cognitive
activity; an operation that affects mental contents; "the
process of thinking"; "the cognitive operation of
remembering" [syn: process, cognitive process, {mental
process}, operation, cognitive operation]
10: (mathematics) calculation by mathematical methods; "the
problems at the end of the chapter demonstrated the
mathematical processes involved in the derivation"; "they
were learning the basic operations of arithmetic" [syn:
mathematical process, mathematical operation,
operation]
11: the activity of operating something (a machine or business
etc.); "her smooth operation of the vehicle gave us a
surprisingly comfortable ride"
From The Collaborative International Dictionary of English v.0.48 [gcide]:
Operation \Op`er*a"tion\, n. [L. operatio: cf. F. op['e]ration.]
1. The act or process of operating; agency; the exertion of
power, physical, mechanical, or moral.
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The pain and sickness caused by manna are the
effects of its operation on the stomach. --Locke.
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Speculative painting, without the assistance of
manual operation, can never attain to perfection.
--Dryden.
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2. The method of working; mode of action.
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3. That which is operated or accomplished; an effect brought
about in accordance with a definite plan; as, military or
naval operations.
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4. Effect produced; influence. [Obs.]
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The bards . . . had great operation on the vulgar.
--Fuller.
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5. (Math.) Something to be done; some transformation to be
made upon quantities or mathematical objects, the
transformation being indicated either by rules or symbols.
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6. (Surg.) Any methodical action of the hand, or of the hand
with instruments, on the human body, to produce a curative
or remedial effect, as in amputation, etc.
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Calculus of operations. See under Calculus.
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