Within the scope of activities that CNXT is currently focused on, the relevant definition for nanotechnology is the research and technology development of new or improved systems based on the synthesis, structuring, modification, or manipulation of matter at some critical length scale in the range of 1 - 100 nanometers. These processes may be at the atomic or molecular level. The essential feature here is the emergence of new, novel, or improved properties when the typical feature size associated with the matter is in the nanometer-scale. Nanometer-scale feature size alone, without new, novel, or improved useful properties, does not constitute nanotechnology.
There are several other operational definitions of nanotechnology in the field. One of the most widely accepted is based on the working documents of the US National Nanotechnology Initiative (NNI). The National Science Foundation, a member of the NNI organization, uses the following version of the definition:
"Research and technology development at the atomic, molecular or macromolecular levels, in the length scale of approximately 1-100 nanometer range, to provide a fundamental understanding of phenomena and materials at the nanoscale and to create and use structures, devices and systems that have novel properties and functions because of their small and/or intermediate size. The novel and differentiating properties and functions are developed at a critical length scale of matter typically under 100nm. Nanotechnology research and development includes manipulation under control of the nanoscale structures and their integration into larger material components, systems and architectures. Within these larger scale assemblies, the control and construction of their structures and components remains at the nanometer scale."
The supporting documents of this definition can be found at the National Science Foundation website.