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.
Security
Security is freedom from, or resilience against, potential harm (or other unwanted coercive change) from external forces. Beneficiaries (technically referents) of security may be persons and social groups, objects and institutions, ecosystems, and any other entity or phenomenon vulnerable to unwanted change by its environment.
Security
From that point, my universe went on crumbling; new cracks appeared all the time. I could see that the pleasant securities of childhood, all of those warm little human emotions, all of those trivial aims and purposes that we allow to rule our lives, were an illusion. We were like sheep munching grass, unaware that the butcher's lorry is already on its way. I got used to living with a deep, underlying feeling of uncertainty that no one around me seemed to share. It was rather like living on death row.
Colin Wilson in Alien Dawn, pp. 12-13 (1998)