Nanotechnology: a general term covering nanoscale science and engineering. A more narrow definition is miniaturization engineering at the nanometer scale. Nano is a metric prefix meaning 'billionth', in this case, science, technology, and engineering at sizes measured in billionths of a meter, which is 1,000 times smaller than a micrometer. It is proposed to build electronic and mechanical devices which are made of very tiny parts (as are biotic systems), but which may have very large effects (as do biotic systems).