Nano-
Nano- (symbol n) is a unit prefix meaning "one billionth". Used primarily with the metric system, this prefix denotes a factor of 10−9 or 0.000000001. It is frequently encountered in science and electronics for prefixing units of time and length.
Examples:
The prefix derives from the Greek (Latin nanus), meaning "dwarf". The General Conference on Weights and Measures (CGPM) officially endorsed the usage of nano as a standard prefix in 1960.
When used as a prefix for something other than a unit of measure (as for example in words like "nanoscience"), nano refers to nanotechnology, or means "on a scale of nanometres". See nanoscopic scale.
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