n. Originally, the art of managing engines; in its modern and extended sense, the art and science by which the properties of matter are made useful to man, whether in structures, machines, chemical substances, or living organisms; the occupation and work of an engineer. In the modern sense, the application of mathematics or systematic knowledge beyond the routine skills of practise, for the design of any complex system which performs useful functions, may be considered as engineering, including such abstract tasks as designing software (software engineering).