operation in WordNet English dictionary

1. (psychology) the performance of some composite cognitive activity; an operation that affects mental contents
   "the process of thinking"; "the cognitive operation of remembering"
   process  cognitive process  mental process  operation  cognitive operation 
   
2. 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"
   operation  functioning  performance 
   
3. (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"
   mathematical process  mathematical operation  operation 
   
4. activity by a military or naval force (as a maneuver or campaign)
   "it was a joint operation of the navy and air force"
   operation  military operation 
   
5. 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"
   operation  surgery  surgical operation  surgical procedure  surgical process 
   
6. 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"
   operation 
   
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"
   operation  procedure 
   
8. 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"
   operation 
   
9. the activity of operating something (a machine or business etc.)
   "her smooth operation of the vehicle gave us a surprisingly comfortable ride"
   operation 
   
10. (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"
    operation 
    
11. the state of being in effect or being operative
    "that rule is no longer in operation"
    operation