Combat
Combat (French for fight) is a purposeful violent conflict meant to weaken, establish dominance over, or kill the opposition, or to drive the opposition away from a location where it is not wanted or needed.
Engineering
Engineering is the creative application of science, mathematical methods, and empirical evidence to the innovation, design, construction, operation and maintenance of structures, machines, materials, devices, systems, processes, and organizations. The discipline of engineering encompasses a broad range of more specialized fields of engineering, each with a more specific emphasis on particular areas of applied mathematics, applied science, and types of application. See glossary of engineering.