1. The act or process of operating or functioning. 2. a factory in operation. 3. the operation of building a house. 4. That restaurant is quite an operation. 5. a fencing operation for stolen goods. 6. A surgical procedure for remedying an injury, an ailment, a defect, or a dysfunction. 7. A process or an action, such as addition, substitution, transposition, or differentiation, performed in a specified sequence and in accordance with specific rules. 8. An action resulting from a single instruction. 9. A military or naval action, campaign, or mission. 10. The headquarters or center from which a military action, flights into and out of an airfield, or other activities are controlled. 11. The division of an organization that carries out the major planning and operating functions.
