an American operation in World War I (1918); American troops under Pershing drove back the German armies which were saved only by the armistice on November 11 | a medical procedure involving an incision with instruments; performed to repair damage or arrest disease in a living body |
a European river; flows into the North Sea | (mathematics) calculation by mathematical methods |
| activity by a military or naval force (as a maneuver or campaign) |
| a planned activity involving many people performing various actions |
| a process or series of acts especially of a practical or mechanical nature involved in a particular form of work |
| a business especially one run on a large scale |
| the activity of operating something (a machine or business etc.) |
| (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 |